Former Browns center J.C. Tretter announces his retirement
The NFL cast JC Tretter out; the NFLPA president says that only makes him more powerful - Sports Illustrated
JC Tretter Retires from NFL at 31; Former Packers, Browns Center Is NFLPA President, News, Scores, Highlights, Stats, and Rumors
JC Tretter, NFLPA president and former Browns center, retires after nine seasons
Tretter re-elected president of NFL union
JC Tretter, former Cleveland Browns center, retires after 8 seasons in NFL but remains NFLPA president - ESPN
The NFL cast JC Tretter out; the NFLPA president says that only makes him more powerful - Sports Illustrated
3 Reasons Browns Offensive Line Can Be Even Better In 2021
Former Browns center JC Tretter retiring after 8 NFL seasons, will stay on as NFLPA president
[JC Tretter] Thank you, Cleveland : r/Browns