John William Hennessy (born March 12, 1955) is an American former professional football player.
He attended high school at Gordon Tech, now known as DePaul College Prep in Chicago.
[2][3][4] He started all 12 games at defensive tackle for the 1976 Michigan Wolverines football team.
The 1976 Michigan team won the Big Ten Conference championship, advanced to the 1977 Rose Bowl, and finished the season ranked No.
The following year, he was a starter at linebacker in all 16 regular season games for the 1978 New York Jets.