James Thomas Mahoney (born on May 26, 1934 in Englewood, New Jersey) is a former Major League Baseball shortstop. He was signed by the Philadelphia Phillies before the 1953 season and played for the Boston Red Sox (1959), the Washington Senators (1961), Cleveland Indians (1962), and Houston Astros (1965).
Mahoney was the first player to appear as a pinch runner in modern Washington Senators history. On April 10, 1961, in the bottom of the 9th, he came into the game to run for second baseman Danny O'Connell, who had singled with one out. He reached second on an R. C. Stevens grounder to third, but did not score, as the next batter made the third out. The Washington Senators lost to the Chicago White Sox, 4-3.
Other career highlights include:
- one 3-hit game...three singles and two runs scored in a 9-4 victory over the Detroit Tigers (May 11, 1961)
- a home run vs. the New York Yankees in front of 70,918 fans at Cleveland Stadium (June 17, 1962)
- hit a combined .381 (8-for-21) against All-Stars Eddie Fisher, Mike Fornieles, Mudcat Grant, and Dave Stenhouse
Mahoney was a good defensive shortstop and second baseman (.966 fielding percentage), but not a strong hitter. In his short career, he had a lifetime batting average of .229 with 4 home runs, 15 RBI, and a slugging percentage of .314 in his 210 at bats. He scored 32 runs in 120 ballgames.
After his playing career, he was a Major League coach for the Chicago White Sox (1972–76) and Seattle Mariners (1985–86), and managed in the farm systems of the White Sox, Pittsburgh Pirates and Minnesota Twins.