Robert F. "Ace" Gruenig (March 12, 1913 – August 11, 1958) was an American basketball player during the 1930s and 1940s.
(203 cm) Gruenig is considered one of the game's first great big men.
The Chicago, Illinois native led his high school, Crane Tech, to the Chicago Public High School League championship in 1931.
He attended Northwestern University, but withdrew after his freshman year without having played for the varsity.
This biographical article relating to a United States basketball player, coach, or other figure born in the 1910s is a stub.