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From BR Bullpen
Capacity (final figure): 56,000
Dimensions: 279 left foul line, 258 right field foul line, 447 right nook, 440 left nook, 483 dead center
(Upper deck overhung field fence, therefore a HR could be shorter than the marked distance.)
Hitter or Pitcher Park?: Both
First Game: 1911
Last Game: 1964
New York Yankees Home Record: 416-335-10
There were more than one Polo Grounds. The one that we know and love, the immortal home of the New York Giants (and temporary homes of the New York Yankees and New York Mets), was the fifth incarnation of the Grounds, the original ones of which were actually used to play polo. It was called Brush Stadium, but the name Polo Grounds stuck. Despite its rectangular shape much better suited for football (and indeed football was played there, notably the New York Giants and the New York Titans, later to be known as the Jets), the Polo Grounds were designed with baseball first in mind.
Only two stadiums, the Polo Grounds and Sportsman's Park, have played exclusive host to the World Series, being the home field of both the Yankees and the Giants in the 1921 and 1922 World Series. In 1923 the Giants evicted the Yankees, who went on to build the classic Yankee Stadium less than a mile away across the Harlem River.
To call this stadium quirky would be an understatement, as the ballpark is one big quirk. The distances down the foul lines are obscenely short yet there were no tall fences to prevent easy home runs, which should have made this a hitter's dream, but at the same time the fences went straight back to a maximum distance of 483 feet to the center field clubhouse. The clubhouse itself at 515 feet to home and 60 feet high had no home run line on it and it was unclear as to whether a batted ball hitting the roof would have been a home run. Some speculate that the ball needed to clear the fence at the back of the structure, an additional 90 feet. Since no one ever reached the top of the front wall the question has gone unanswered. These idiosyncracies should have made this stadium a pitcher's delight. So the Polo Grounds' hitter/pitcher alignment depends on where the ball is hit. Only four people have hit home runs into center field (Hank Aaron and Lou Brock, on consecutive days, and Joe Adcock). To add to the bonanza of oddities, the bullpens are in play in the nooks of the outfield wall. One could reason that they could have put the bullpens behind fences or into the foul territory, but for whatever reason the Giants did not do either.
 Further Reading
- Stew Thornley: "The Polo Grounds", The National Pastime, SABR, Number 20 (2000), pp. 35-38.