This is what we found on Wikipedia regarding the Oscar Blue:

Oscar Levant (December 27, 1906 – August 14, 1972) was an American concert pianist, composer, conductor, author, radio game show panelist, television talk show host, comedian, and actor. He had roles in the films Rhapsody in Blue (1945), The Barkleys of Broadway (1949), An American in Paris (1951), and The Band Wagon (1953). He was awarded a star on the Hollywood Walk of Fame in 1960 for recordings featuring his piano performances. He was portrayed by Sean Hayes in the Broadway play Good Night, Oscar, written by Doug Wright. Levant appeared as himself in the Gershwin biopic Rhapsody in Blue (1945).