Major League Baseball Player. Played Major League Baseball as an outfielder for 12 seasons (1925, 1928 to 1938) with the Pittsburgh Pirates, Philadelphia Athletics and Chicago White Sox. Played 4 games for the Pirates in 1925 before returning to the Minors, and emerging in 1928 with the Athletics. He divided his playing time with future Hall of Famer Tris Speaker, who was in his last season, and who brought Mule Haas under his tutelage. He responded to Speaker's lessons in 1929 by hitting .313, and helping the A's win the American League Pennant, which would be the first of three consecutive trips for the A's to the Fall Classic. In the 1929 World Series, against the Chicago Cubs, he batted .238, hit 2 Home Runs and knocked in 6 RBIs. In Game 4, he hit an inside-the-park home run off of Art Nehf that outfielder Hack Wilson lost in the sun at Shibe Park (to date it is the last Home Run of its kind to be hit in World Series play). It was part of a 10-run 7th Inning that would eventually win the game for the A's. In Game 5, he hit ninth-inning, two-run Home Run off Pat Malone that tied the game. The A's would then win the Game and the Series later in the same inning. The next two seasons he would hit .299 and .323, and help the A's to two more World Series trips, although his post-season appearances would not equal his initial one. Against the St. Louis Cardinals in 1930, he would bat only .111 in the A's 4 Games to 2 Championship victory. In 1932, in a re-match against the Cards, he batted .130 as the Cardinals, fueled by Pepper Martin's amazing hitting performance, avenged their previous year's loss, taking the Series 4 Games to 3. After the end of the 1932 season, A's manager Connie Mack broke up his stellar team, selling Mule Haas, Jimmy Dykes, and future Hall of Famer Al Simmons to the White Sox. He would spend the next five seasons with Chicago, but would never equal his success he had with the A's. His highest batting average with the Sox would be .291 in 1935. After hitting only .207 and being relegated to the bench in 1937, he was released. In 1938 he rejoined the Athletics for a 40-game stint that saw him most used mostly as a pinch hitter before he retired for good. His career totals were 1,168 Games Played, 1,257 Hits, 706 Runs, 43 Home Runs, 496 RBIs and a .292 career Batting Average.