Born in 1956 in Queens, New York, Greg Cosell grew up in Flushing, approximately ten minutes from Shea Stadium, as the only child in a middle-class family. He was an all-city shortstop and basketball player at Francis Lewis High School. He is the nephew of iconic broadcaster Howard Cosell, though he emphasizes their relationship was familial rather than professional, limited by geography and his uncle's demanding schedule. Cosell attended Amherst College in Massachusetts, where he played basketball and majored in American history and political science, graduating in 1978. After a year teaching high school and coaching baseball in Michigan, where he helped lead his team to a state championship as third base coach, he applied to NFL Films on a whim and was hired by founder Ed Sabol as a producer in January 1979.