Monaco was a powerful guard who led the way for a number of Holy Cross Hall of Fame backs, incudling Bill Osmanski, Joe Osmanski, Ronnie Cahill and Hank Giardi. He was also a member of the Crusader baseball team. After graduation he played two seasons in professional football, one for the Washington Redskins and the other for the Cleveland Rams. After his playing career was over he practiced law, helping obtain pensions for retired football professionals. He also served on National League Football Alumni Association.