George William "Mule" Haas (October 15, 1903 – June 30, 1974) was an American professional baseball player. He played as a center fielder in Major League Baseball from 1925 through 1938, most notably as a member of the Philadelphia Athletics dynasty that won three consecutive American League pennants from 1929 to 1931 and won the World Series in 1929 and 1930.