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In the first season, the league played a game that was a hybrid of baseball and softball. The ball was 12 inches in circumference, the size of a regulation softball (regulation baseballs are 9 to 91⁄4 inches). The pitcher's mound was only forty feet from home plate, closer even than in regulation softball and much closer than the baseball distance of 60 feet, 6 inches. Pitchers threw underhand windmill, like in softball, and the distance between bases was 65 feet, five feet longer than in softball, but 25 feet shorter than in baseball. Major similarities between the AAGPBL and baseball included nine player teams and the use of a pitcher's mound (softball pitchers throw from flat ground). By 1948, the ball had shrunk to 103⁄8 inches, overhand pitching was allowed, and the mound was moved back to 50 feet. Over the history of the league, the rules continued to gradually approach those of baseball. By the final season in 1954, the ball was regulation baseball size, the mound was moved back to 60 feet, and the basepaths were extended to 85 feet (still five feet shorter than in regulation baseball).