Clay Matthews III is making a major push to get his dad into the Pro Football Hall of Fame -- saying the guy checks off all the boxes needed to punch a ticket to Canton.
The legendary Cleveland Browns linebacker has been eligible for the Hall for 20 years, and 2021 marks his last opportunity for selection by the Modern era committee.
Clay's son -- who also had a long and successful career in the NFL with the Green Bay Packers and L.A. Rams -- is going to bat for his old man ... explaining why he's long overdue for the recognition.