Brooklyn born and raised, Mullin stayed close to home when he enrolled at St. John's. He was a three-time Big East Player of the Year and the Red Storm's all time leading scorer. 1985 was a banner year for Mullin as he led his team to the Final Four and earned the John R. Wooden Award as the nation's best player. He won Olympic gold in 1984 and 1992 as a member of the Dream Team.

St. John's University Men's BB Head Coach