Mapes, who was listed with a height of 6 ft 3 in (1.91 m), and a weight of 205 lb (93 kg), was originally signed as an amateur free agent by the Cleveland Indians prior to the 1940 season. He never played for the Indians, and was later drafted by the New York Yankees in the 1946 Rule 5 draft. After a season in the minors, Mapes was recalled to the Major League level, where he saw limited time as a backup to an outfield that contained Joe DiMaggio, Tommy Henrich, and Johnny Lindell. Mapes hit .250, with 12 runs batted in, and his first career home run.

In his second season, Mapes saw regular time as a starter. He hit .247 with seven home runs and 38 runs batted in, but also led the team in strikeouts in helping the Yankees claim the American League pennant. He was the team's starting right fielder against the Brooklyn Dodgers, and he helped the team win the 1949 World Series, the team's first World Series en route to five consecutive world championships.

In 1950, Mapes led the team in strikeouts for the second consecutive season. His playing time remained the same, but his power numbers improved from a year earlier. Mapes hit batted .247 with 12 home runs and 61 runs batted in, but also grounded into a team-high 14 double plays. The Yankees finished the season with the American League pennant once again, but Mapes saw little time in the postseason; Mapes only appeared in one game as the Yankees won the 1950 World Series in a four-game sweep of the Philadelphia Phillies.

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Wikipedia