Lefty Grove, byname of Robert Moses Grove (born March 6, 1900, Lonaconing, Md., U.S.—died May 22, 1975, Norwalk, Ohio), American professional baseball player, one of the greatest left-handed pitchers in history.
He grew up in a mining town and worked odd jobs when his formal education ended after the eighth grade. Grove did not play organized baseball until age 19. He began his professional career in 1920, winning 108 games for the minor league Baltimore Orioles of the International League before his contract was bought by Connie Mack of the American League (AL) Philadelphia Athletics (A’s) in 1924 for $100,600, a record sum at the time. Grove debuted for the A’s the following year at age 25 and led the league in strikeouts, the first of seven consecutive seasons in which he topped the AL in that category.
Not until he mastered control of his pitches, however, did he become a star pitcher of his era. From 1927 through 1933 Grove won at least 20 games each season, and he led the league in earned run average (ERA) on five occasions as an Athletic (1926, 1929–32). In 1931 he was 31–4 with a career-low 2.06 ERA and won the AL Most Valuable Player award. In addition to his standout individual accomplishments, Grove was a key contributor on two A’s World Series championship teams (1929–30).
Mack was forced to sell Grove to the Boston Red Sox in 1934. After a disappointing and injury-plagued first season in Boston, Grove regained a good measure of his original form and led the AL in ERA four times (1935–36, 1938–39) in his eight seasons with the team. He retired in 1941 with career totals of 300 wins, 141 losses, a 3.06 earned run average, and 2,266 strikeouts. In 1947 Grove was elected to the Baseball Hall of Fame in Cooperstown, N.Y.