 Koenecke made his debut for the Giants, going hitless against the Philadelphia Phillies on April 12, 1932

In 1933, playing for the International League Buffalo Bisons, he hit .334 and drove in 100 runs batted in with eight home runs.In 1934, Koenecke joined the Brooklyn Dodgers, where in his first season he hit 14 home runs, 73 RBIs and set a National League fielding record with a percentage of .994.His second season saw a decline in his onfield performance and his drinking became a problem to the point where he was cut on September 16, 1935, during the middle of a road trip after a game in Chicago.