MLB Park Factors and the Impact on Batters

A lot of people look at the Steroids/PEDs use of the late 1980s and early 1990s for influencing the home run boom of the modern era. Other people look at the past and see legitimate names such as Hank Aaron or Roger Maris and argue their numbers were far more pure.

Forgotten, ignored, or just unrealized in these debates are the impacts of changing fence dimensions of ballparks. A quiet element that has been going on since the creation of baseball and ballpark designs as we know it. It’s common knowledge that closer fences will reciprocate with more home runs hit.

The Old Ballparks of the 1920s, 1930s, and 1940s

A lot of the old baseball stadiums were known as much for their cavernous center fields where it was not uncommon to see dimensions going well over 500 feet and over 450 feet in the power alleys of left and right center field.

From 1913 to 1949, Shibe Park aka Connie Mack Stadium, home to the Philadelphia Athletics and later Philadelphia Phillies, saw its dimensions change in part to accommodate the burgeoning home run spectacle of hitters such as Babe Ruth, Loe Gehrig, and Jimmie Foxx.

1913: LF Line was 360. RF Line was 340. CF was 509.
1930: LF Line was 334. RF Line was 331. CF was 468.
1949: LF Line was 334. RF Line was 329. CF was 447. Power alleys had shortened to roughly 360 and 355 feet.

It was not the only park to start radically changing. Ebbets Field, the infamous home of the Brooklyn Dodgers, had also undergone fairly drastic changes pulling its fences much closer by the 1940s as well.

1913: LF Line was 419. RF Line was 301. CF was 508.
1926: LF Line was 389. RF Line was 301. CF was 500.
1932: LF Line was 365. RF Line was 298. CF was 405. Power alleys were roughly 365 and 335.
1948: LF Line was 348. RF Line was 297. CF was 390. Power alleys were roughly 351 and 335.

One hitter, Lefty O’Doul would take advantage in 1932 hitting 13 home runs at Ebbets Field. Jackie Robinson was also impacted by the dramatically shortening walls during his career at Ebbets Field in the late 1940s and early 1950s, hitting 78 home runs at home against just 59 on the road.

Tris Speaker took advantage of Fenway Park’s earlier spacious dimensions hitting .338 from 1908-1915 for the Red Sox before being traded to Cleveland. Speaker, a left handed hitter, instantly took advantage of the far shorter 290 foot right field line and 320 feet to the right center field power alley as League Park was built much like Yankee Stadium and was death to power hitting right handed hitters. Speaker ended up hitting .354 with 73 home runs for Cleveland from 1916-1926 including 17 home runs (10 at home) at age 35 in 1923.

Tris Speaker at Fenway Park Career: .331/.415/.446 with 73 Doubles and 1 HR in 991 AB
Tris Speaker at League Park Career: .383/.476/.575 with 320 Doubles and 37 HR in 2,835 AB

Babe Ruth’s Power Surge in the 1920s and 1930s

Ruth was a star pitcher but gradually became known for his power by 1918 when he slugged 11 home runs and followed that up with 29 in 1919. During his two years there, Fenway was 302 down the right field line but a much deeper 365-370 feet to the power alley. Ruth did not hit any home runs at Fenway in 1918 and mustered just 9 during the 1919 season.

Then came the trade where Ruth was sent to Yankee Stadium and the New York Yankees. It’s worth noting that in a lot of ways, Ruth’s abilities were a pre-cursor to the heavily asked “what if?” question that I’ll be mentioning later with Ted Williams. Initially, Ruth and the Yankees played at the infamous Polo Grounds which featured an oddball U shape but left a 258 foot right field line with the right side stretching up to 350 feet at the power alley, giving Ruth plenty of space to clout home runs. From 1923 to 1928, the right field line at Yankee Stadium gradually shifted from 258 feet to 295 feet with the right center field power alley moving in from roughly 355 feet to 350 feet. The effects of these closer fences were instantaneous for Ruth.

Fenway Park 1918: 0 Home Runs of 11 Total
Fenway Park 1919: 9 Home Runs of 29 Total
Polo Grounds 1920: 29 Home Runs of 54 Total
Polo Grounds 1921: 32 Home Runs of 59 Total
Polo Grounds 1922: 14 Home Runs of 35 Total
Yankee Stadium 1923: 19 Home Runs of 41 Total
Yankee Stadium 1924: 24 Home Runs of 46 Total
Yankee Stadium 1925: 11 Home Runs of 25 Total
Yankee Stadium 1926: 23 Home Runs of 47 Total
Yankee Stadium 1927: 28 Home Runs of 60 Total
Yankee Stadium 1928: 29 Home Runs of 54 Total
Yankee Stadium 1929: 21 Home Runs of 46 Total
Yankee Stadium 1930: 26 Home Runs of 49 Total
Yankee Stadium 1931: 24 Home Runs of 46 Total
Yankee Stadium 1932: 19 Home Runs of 41 Total

During that period of time, Ruth ended up hitting 603 home runs total. At the Polo Grounds alone in just 3 seasons, Ruth hit 75 home runs at home. Much like later power hitters such as Hank Aaron, Mark McGwire, Sammy Sosa, and Barry Bonds, Ruth took advantage of the closer fences at Yankee Stadium and it helped turn him into arguably the most prolific home run hitter of all time.

Fenway Park % of Home Runs: 2.25
Polo Grounds % of Home Runs: 5.07
Yankee Stadium % of Home Runs: 4.92

The infamous Murderer’s Row of 1927 took advantage of Yankee Stadium as a team, hitting 158 home runs total (102 more than the next highest team, the Philadelphia Athletics). Even ignoring Ruth and Gehrig, just the combination of Lazzeri/Combs/Collins/Meusel managed to slug out 23 home runs at Yankee Stadium nearly matching the entire totals for the Cleveland Indians (26) and Boston Red Sox (28).

Babe Ruth (LH): 28 Home Runs
Lou Gehrig LH): 24 Home Runs
Tony Lazzeri (RH): 11 Home Runs
Earle Combs (LH): 5 Home Runs. Also hit 14 Doubles and 10 Triples.
Pat Collins (RH): 4 Home Runs
Bob Meusel (RH): 3 Home Runs

Speaking of Murderer’s Row, Lou Gehrig also took advantage of Yankee Stadium’s short fences hitting .329 with 251 home runs there for his entire career. For comparison, Gehrig hit 242 on the road including just 27 in 552 AB in Fenway Park.

Hank Greenberg and the Subtle Changes in Detroit’s Navin Field aka Briggs Stadium/Tiger Stadium

In a curious inverse of most baseball stadiums, Navin Field started out catering more towards right handed hitters by 1926 with 341 foot down the left field line and 370 feet to the left center field power alley in comparison to 371 and roughly 390 feet on the opposite side. Changes continued by 1934, shortening the lines down to 339 and 367 feet and by 1936, right field had undergone a massive overhaul shortening its right field line to just 325 with 370 to the power alley. These changes would largely remain for the duration of the park’s existence with the exception of shortening center field to 440 feet in 1938.

Greenberg was one of the earliest icons for the Detroit Tigers during the 1930’s with seasons of 36, 40, 58, 33, 41, and 44 home runs. Thanks to the more favorable conditions of the left field dimensions in comparison to most ballparks of the era, Greenberg immediately took advantage.

1934: Greenberg would hit 15 HR and bat .364
1937: Greenberg would hit 25 HR and bat .383
1938: Greenberg would hit 39 HR and bat .350
1939: Greenberg would hit 16 HR and bat .336
1940: Greenberg would hit 27 HR and bat .394
1946: Greenberg would hit 29 HR and bat .276

If not missing multiple years for World War 2, it’s not too inconceivable that Greenberg could have added more than 75 home runs to his career totals given how advantageous Navin Field/Briggs Stadium had been to his hitting style. Instead of just hitting 331 home runs, Greenberg could have hit well over 400 for his career and possibly flirted with as many as 420 home runs.

Ted Williams and Fenway Park vs. Joe DiMaggio and Yankee Stadium

A favorite argument for baseball fans is what would happen if you had put Ted Williams in Yankee Stadium and Joe DiMaggio in Fenway Park for their entire careers instead. What is commonly unrealized is the radical shift of the ballparks themselves.

Fenway Park, by 1926 and into the 1930s, was far more spacious than fans think. The “short” right field porch was actually 358 feet down the line while the Green Monster was situated 320 feet down the left field line. Center field was a robust 426 feet at its deepest. By 1934, the fences had been moved in slightly to 389 feet at center field and 312 feet/334 feet respectively down the left and right field lines.

The biggest impact came by the 1940 season when Fenway Park finally settled into the dimensions it’s still known for today. Center field now settles at 390 feet straightaway from home plate while the Green Monster sits at a scant 315 feet and the right field porch is only 302 feet away. Williams, a left handed hitter, would finish his career with only 248 home runs at home despite a .361 BA in large part thanks to the 380 foot right center field power alley. On the road, Williams would hit 273 home runs and still average .328.

Unlike Fenway Park’s short left field to the Green Monster, Yankee Stadium was far more welcoming to left handed batters with a short 296 line to the right field porch and just 367 feet to the power alley by 1938. Unfortunately for right handed hitters such as Joe DiMaggio, the left field line was just 301 feet but the power alley was an insane 415 feet and center field was 461 feet straightaway. These dimensions would largely stay the same until the mid 1970’s.

DiMaggio was far more impeded by the cavernous left field of Yankee Stadium and wound up his career hitting just 148 home runs with a .315 BA in comparison to hitting an impressive 213 home runs on the road with a .333 batting average. It is fair to say that DiMaggio probably could have finished his career with at least 70 more home runs than he actually did (361) if he had played at Fenway Park. At Fenway, Joe averaged a home run in 6% of his at bats compared to just 4.4% at Yankee Stadium.

Hank Aaron and the Atlanta-Fulton County Stadium Effect

Aaron spent a large portion of his career with the Milwaukee Braves during the 1950s and early 1960s, routinely hitting 35-45 home runs in a given season while capably driving in 120+ runs a year like clockwork. From 1957-1963 alone he would hit an impressive 276 home runs with a .323 batting average.

The Braves would move to Atlanta in 1966 and also change ballparks to Atlanta-Fulton County Stadium, a spacious ballpark with a solid, reminiscent feel to modern day ballparks including 405 feet to center field and 385 feet to the left and right center field power alleys. From 1966-1968, Aaron would hit 112 home runs with a solid enough .291 batting average considering he was 34 years old by the end of 1968.

Quietly unnoticed by most fans, the dimensions would change in 1969. The outfield fence was moved in, changing center field to just 400 feet and reducing the power alleys to 375 feet. This change would remain through the 1973 season and have an immediate impact on Aaron. From 1969-1973 he would hit 203 home runs with a .299 batting average and never hit fewer than 34 home runs in a given year (in 1968 he hit 29, his fewest since 1964 when he hit 24).

Here are how his numbers stacked up comparing hitting at Atlanta-Fulton County Stadium vs. on the road.

1966: 21 HR and .269 BA vs. 23 HR and .288 BA
1967: 23 HR and .350 BA vs. 16 HR and .268 BA
1968: 17 HR and .299 BA vs. 12 HR and .276 BA
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1969: 21 HR and .308 BA vs. 23 HR and .292 BA
1970: 23 HR and .274 BA vs. 15 HR and .322 BA
1971: 31 HR and .346 BA vs. 16 HR and .310 BA
1972: 19 HR and .249 BA vs. 15 HR and .281 BA
1973: 24 HR and .317 BA vs. 16 HR and .283 BA
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1974: 11 HR and .297 BA vs. 9 HR and .240 BA

The fences were moved back to their original 402 feet and 385 feet in 1974 and Aaron’s power fell immediately. While rather comparable from 1966-1968 and 1974, Aaron had a largely distinct advantage hitting at home when the fences were moved in by just 10 feet. During that time, he would hit 118 HR at home compared to just 85 on the road while being well into his late 30’s.

Impact of Ballparks in the 1970s and 1980s

As mentioned earlier, Yankee Stadium underwent an overhaul by 1976, shortening the power alleys to 385 and 387 feet. Center field was also shortened to 417 feet.

In 1985, the fences were altered even more as left center field’s power alley was shortened to 368 feet and by several more feet in 1988.

The effects were almost immediately felt, especially at Yankee Stadium where the home run levels were rising for both the home team as well as visiting opponents.

1973: 116 Home Runs at Yankee Stadium
1974: 92 Home Runs at Yankee Stadium
1975: 106 Home Runs at Yankee Stadium
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1976: 118 Home Runs at Yankee Stadium
1977: 147 Home Runs at Yankee Stadium
1978: 127 Home Runs at Yankee Stadium
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1985: 159 Home Runs at Yankee Stadium
1986: 189 Home Runs at Yankee Stadium
1987: 186 Home Runs at Yankee Stadium
1988: 152 Home Runs at Yankee Stadium
1989: 152 Home Runs at Yankee Stadium

In 1977, Seattle managed to earn a baseball team and quickly found out that their stadium greatly aided left handed hitters, an acknowledgement that would prove incredibly notable by the 1990’s. Even as early as its debut year, left handed hitters were taking advantage of the short 316 foot right field line and 23 foot high fence.

1977: Ruppert Jones hit 17 HR at the Kingdome vs. 7 HR on the road.
1979: Ruppert Jones hit 17 HR at the Kingdome vs. 4 HR on the road.
1983: Pat Putnam hit 11 HR with 16 Doubles at the Kingdome vs. 8 HR and 7 Doubles on the road.
1984: Alvin Davis hit 15 HR with 21 Doubles at the Kingdome vs. 12 HR and 13 Doubles on the road.
1987: Alvin Davis hit 18 HR with 17 Doubles at the Kingdome vs. 11 HR and 20 Doubles on the road.

The Seattle Kingdome had undergone a rather unique transformation just in time for rising star Ken Griffey Jr, a lefthanded home run masher with one of the purest swings in baseball. By 1991, just 2 years after Griffey Jr had been called up, the ballpark began to favor left handed batters even more. The right field line had shrunk down to just 312 feet and the right field center power alley was pushed back just slightly to a still short 355 feet. During his career there from 1989-1999, Ken Griffey Jr would hit 198 home runs with a .310 BA.

From 1996-1998, Junior hit 49, 56, and 56 home runs. At the Kingdome he would hit 26, 27, and 30 home runs while being able to utilize the big wall for singles and doubles much like Fenway Park’s Green Monster.

Edgar Martinez, a longtime teammate and right handed hitting designated hitter, would only hit 95 home runs but .321 with 194 doubles as a result of the more spacious left field area. Another right handed hitter and longtime teammate to Ken Griffey Jr was Jay Buhner. During his career with the Mariners, he would hit only 125 home runs at the Seattle Kingdome with 164 home runs on the road.

Mile High Stadium Transitioning To Coors Field and the HR Boom of the 1990s

Mile High Stadium came with the Colorado Rockies in 1993, despite being a baseball stadium for minor league teams in Denver since the late 1940s. It was an immediate favorable design for right handed hitters thanks to a 333 foot line and 366 left center power alley combining with the thin air (in comparison to 370 and 395 for left handed hitters).

Right handed power hitters immediately took advantage of Mile High Stadium in its two year existence in baseball. Interestingly, Larry Walker, a left handed hitter, was capable of some great power seasons but was as known for his ability to hit for a high batting average with a greater ability to hit doubles (much like Todd Helton later on in baseball history).

Andres Galarraga: 13 HR with .420 BA and 16 HR with .348 BA
Dante Bichette: 11 HR with .373 BA and 15 HR with .353 BA
Charlie Hayes: 17 HR with .338 BA and 4 HR with .317 BA
Vinny Castilla: 5 HR with .305 BA and 1 HR with .344 BA in part time play

In 1995, the Colorado Rockies would move into Coors Field, which provided similar dimensions to right handed hitters (347 LF line and 380 power alley) while slightly accommodating left handed hitters more with a 350 right field line and 375 power alley in right center field.

Other ballparks saw similar favorability aimed towards hitters. Memorial Stadium had long been the home to the Baltimore Orioles with very short lines but a bowl shape and slightly longer power alleys. The creation of Oriole Park in Camden Yards in 1992 saw the power alleys shorten considerably (375 feet down to 364 feet in the left field power alley and 375 feet to 370 feet in the right field power alley) while seeing the lines pushed back to 333 feet on both sides.

In 1995, Kansas City’s Kauffman Stadium moved their power alleys in 10 feet from 385 to 375 feet through the 2003 MLB Season before moving them back in 2004. Jeff King would hit 24 HRs at home in 1997 & 1998 compared to 28 on the road. Chili Davis set a career high with 30 home runs in 1997 but was largely aided by Kauffman Stadium where he slugged 21 HRs to just 9 on the road despite being 37 years old.

Matt William’s and Tony Gwynn’s Chase in 1994

Matt Williams had been hitting at Candlestick Park for a while and continued to benefit from his home park as far back as 1990. He had been consistently putting up seasons with 30+ home runs but that suddenly seemed to change in 1994 when he was on pace to challenge Roger Maris’ record of 61. He had hit 43 HRs and seemingly came on out of nowhere.

1990: Williams hit 20 of his 33 HR at Candlestick Park despite a .272 BA against .283 on the road
1991: Williams took advantage with 17 HR at Candlestick Park and a .287 BA against 17 HRs and .250 on the road
1993: Williams was again a near perfect split with 19 HR and .293 at Candlestick Park vs. 19 and .295 on the road
1994: Williams hit 20 HR at Candlestick Park with a .265 BA vs. 23 HRs and .270 BA on the road

Across the state in San Diego, singles hitter Tony Gwynn was surging like he never had before. Jack Murphy Stadium had never really changed during Gwynn’s career settling down at 327 feet down the lines with 370 feet to the power alleys and 405 feet to center field.

Gwynn had always shown a propensity to hit for a high batting average including 1984 at .351, 1987 at .370, and 1993 at .358. Gwynn followed up his challenge of Ted William’s infamous .406 mark with .368 in 1995, .353 in 1996, and .372 in 1997.

In a lot of ways, Gwynn took advantage of his home park lining singles all over the field as opposed to trying to hit for much power in a stadium where he probably could have taken advantage of the shorter right field line.

1984: Gwynn hit .376 at home including 23 extra base hits.
1987: Gwynn hit .390 at home including 31 extra base hits.
1993: Gwynn hit .382 at home including 26 extra base hits.
1994: Gwynn hit .403 at home including 19 extra base hits. Worth noting is that Gwynn had 21 doubles and 9 HR on the road along with a .387 BA. A bit of an outlier compared to his other seasons.
1995: Gwynn hit .387 at home including 22 extra base hits.
1996: Gwynn hit .351 at home including 20 extra base hits. He actually hit higher, .354, on the road.
1997: Gwynn hit .378 at home including 35 extra base hits.

Gwynn made Jack Murphy Stadium a true home ballpark to rake hits in. In all of those seasons except 1996, he usually had a higher batting average by almost .25 points and more extra base hits except 1994. For his entire career, Gwynn would hit .343 at Jack Murphy Stadium in comparison to .334 on the road.

Barry Bonds and The Advantage of 3-Com Park

Barry Bonds would join the San Francisco Giants in 1993 and see an immediate impact with multiple 40 home run seasons by 1997. This was largely helped by Candlestick Park slightly altering its dimensions from 1972. In what could be argued as somewhat of a coincidence, the right field line was shortened by 7 feet down to 328 and the right center field power alley was shortened from 375 feet to 365 feet. In 1995, the Giants moved into 3-Com Park which was made even more favorable to its star slugger with just 309 feet down the line.

1993: 21 HR and .312 BA at Candlestick Park
1994: 15 HR and .282 BA at Candlestick Park
1995: 16 HR and .307 BA at 3-Com Park
1996: 23 HR and .326 BA at 3-Com Park
1997: 24 HR and .326 BA at 3-Com Park
1998: 21 HR and .325 BA at 3-Com Park

It’s worth noting that while Bonds was equally prolific on the road in terms of power, his BA greatly suffered by comparison. In 1998, he hit just .284 a year after hitting a woeful .257 in 1997. In 1996, he had hit a still solid .291 but nowhere near his numbers at 3-Com Park.

Mark McGwire, Sammy Sosa, and the Home Run Chase of 1998

Mark McGwire had long been a mainstay of the Oakland Athletics. McGwire’s home ballpark of the Oakland Coliseum was long known as a pitcher’s park thanks to a larger than average foul territory that led to easy outs and walls that had not been changed much since 1969: 330 down the lines, 370 feet to the power alleys, and 400 feet to center field. In 1995, McGwire actually hit just 15 HR at the Oakland Coliseum while hitting 24 HR on the road along with a far more robust .297 BA (against .248 at home).

In 1996, Oakland dramatically changed its park introducing various nooks and crannies with the biggest changes coming to the left center and right center power alleys. They were suddenly shortened down to 364 feet with some wall areas shrinking that even further to just 362 feet away. McGwire would feel the impact, hitting 52 home runs of the year along with 24 at home and a .310 batting average. In 1997, McGwire was traded after hitting 17 HR at home with a robust .324 BA.

Upon landing with the St. Louis Cardinals, McGwire found himself at Busch Stadium. The dimensions were nearly identical to the Oakland Coliseum albeit with slightly longer power alleys to 370 feet. McGwire would hit 13 home runs but with just a .286 BA.

Wrigley Field for the Chicago Cubs has largely remained the same dimensions wise since 1938 when center field came in from 447 feet in 1923 to 400 feet. The most interesting change was down the lines which were extended from 325 down left field and 318 down right field to 355 and 353 feet. As the center field distance came closer, the power alleys also became closer down to roughly 365 feet. A large influence was the wind factor, which helped carry balls well over the walls that ordinarily may have been fly ball outs on another day.

Sammy Sosa, a struggling yet massively strong power hitting right hander immediately started taking advantage of the 355 feet down the left field line.

1993: 23 HRs and .272 BA at Wrigley Field vs. 10 HRs and .250 BA on the road
1994: 11 HRs and .285 BA at Wrigley Field vs. 14 HRs and .315 BA on the road
1995: 19 HRs and .272 BA at Wrigley Field vs. 17 HRs and .264 BA on the road
1996: 26 HRs and .282 BA at Wrigley Field vs. 14 HRs and .263 BA on the road
1997: 25 HRs and .269 BA at Wrigley Field vs. 11 HRs and .233 BA on the road

This helps set the stage for the chase of Roger Maris’ record. Sammy Sosa, by the latter 2 years, had a ridiculously enormous split at home in terms of power and Mark McGwire had already been making noise at the Oakland Coliseum and was ready to unload in another stadium with very similar dimensions.

1998 Mark McGwire: 38 HRs and .316 BA at Busch Stadium vs. 32 HRs and .280 BA on the road
1998 Sammy Sosa: 35 HRs and .300 BA at Wrigley Field vs. 31 HRs and .315 BA on the road
1999 Mark McGwire: 37 HRs and .285 BA at Busch Stadium vs. 28 HRs and .272 BA on the road
1999 Sammy Sosa: 33 HRs and .325 BA at Wrigley Field vs. 30 HRs and .252 BA on the road
2000 Mark McGwire: 18 HRs and .342 BA at Busch Stadium vs. 14 HRs and .267 BA on the road
2000 Sammy Sosa: 22 HRs and .306 BA at Wrigley Field vs. 28 HRs and .332 BA on the road

In a lot of ways, Sammy Sosa was arguably a much better pure hitter showing equal power at home and on the road whereas McGwire made a lot of his production capitalizing at Busch Stadium. In 1998 and 1999 combined, McGwire would hit 15 more home runs at home than on the road. By comparison, Sammy Sosa only hit 7 more home runs at Wrigley Field.

2000 and the Introduction of New Ballparks

Several franchises started changing ballparks as 1999 ended and the early 2000’s began. Detroit switched over from Tiger Stadium to Comerica Park, a baseball stadium initially favoring left handed hitters thanks to a 330 line and 365 power alley (vs. right handed hitters facing 345 and 395). By 2005, Comerica Park had moved left center field in to 370 feet offering a more balanced park for hitters.

In 1999, right handed slugger Dean Palmer went from hitting 24 home runs with a .264 BA at Tiger Stadium to hitting 15 HR with a .263 BA at Comerica Park in 2000. Teammate Bobby Higginson, a left handed hitter, went from 10 HR and .291 in 1998 at Tiger Stadium to hitting 12 HR and .333 at Comerica Park in 2000.

After the change in 2005, Detroit would hit 89 home runs at home to just 79 on the road while allowing 86 home runs at home and 107 on the road.

Cincinnati created the Great American Ballpark in 2003 with a balanced approach including 365 feet to the power alleys and 328 feet down the left field line vs. 325 down the right field line. The ballpark immediately became a hitter’s park favoring home runs.

2003: 215 Home Runs at Great American Ballpark vs. 176 Home Runs on the road
2004: 220 Home Runs at Great American Ballpark vs. 210 Home Runs on the road

Minute Maid Park was created for the Houston Astros in 2000 and harkened a lot of influence from Fenway Park with a 315 foot left field line coupled with a 21 foot wall and 365 feet to the left center field power alley. The right field line is 326 feet away and the right field power alley is roughly 368 feet away.

Craig Biggio, Jeff Bagwell, and Lance Berkman all took advantage as right handed hitters or as switch hitters in Berkman’s case.

2000: Biggio hit 2 HR and .259. Bagwell hit 28 HR and .353. Berkman hit 10 HRs and .319.
2001: Biggio hit 10 HR and .316. Bagwell hit 21 HR and .306. Berkman hit 13 HR and .336.
2002: Biggio hit 7 HR and .273. Bagwell hit 16 HR and .299. Berkman hit 20 HR and .320.
2003: Biggio hit 6 HR and .254. Bagwell hit 22 HR and .276. Berkman hit 11 HR and .273.

The Philadelphia Phillies opened Citizens Bank Park in 2004. It immediately became, much like Minute Maid Park, a slugger’s launching pad with 330 feet down the left field line and a 365 foot power alley. This would get pushed back to roughly 370 feet in 2006. The right field line is 330 feet and roughly 365 feet for the power alley.

2004 Citizens Bank Ballpark: 228 Home Runs at home vs. 201 Home Runs on the road
2005 Citizens Bank Ballpark: 201 Home Runs at home vs. 155 Home Runs on the road
2006 Citizens Bank Ballpark: 233 Home Runs at home vs. 194 Home Runs on the road
2007 Citizens Bank Ballpark: 241 Home Runs at home vs. 170 Home Runs on the road

The final major ballpark was the introduction of the new Yankee Stadium in 2009. Like other recent ballparks, the foul lines were incredibly close standing at just 318 and 314 feet away. Right center field’s power alley is roughly 360 feet away and left field’s power alley is roughly 375 feet away thanks to a curvature in the wall. The impact of home runs was so immediate that it raised a national stir with media trying to figure out the cause from wind flow to velocity of balls off the bat.

2009 New York Yankees: Hit 136 home runs at home vs. 108 on the road
2010 New York Yankees: Hit 115 home runs at home vs. 86 on the road
2011 New York Yankees: Hit 122 home runs at home vs. 100 on the road
2012 New York Yankees: Hit 138 home runs at home vs. 107 on the road
2013 New York Yankees: Hit 75 home runs at home vs. 69 on the road
2014 New York Yankees: Hit 88 home runs at home vs. 59 on the road

Modern Day and the Future of Ballparks

Since 2013, we’re already seeing heavily favorable pitchers parks (San Diego Padres, New York Mets) starting to alter their dimensions by bringing the fences in closer in a way to not only improve their team’s performance but also to lure free agents and keep star sluggers on the team without alienating them.

The Oakland Athletics are planning to build a new stadium and the Florida Marlins are already looking into bringing in some of their fences closer.

Moving in the fences closer already has an apparent increase in home runs per game for the altered ballpark and reportedly, the New York Mets are moving their fences in yet again for the 2015 season after having done so for the 2011 season.