Browns center, NFLPA President JC Tretter wanted to make sure players had option to opt out
3 potential replacements for Jaguars C Brandon Linder if he retires
J.C. Tretter Called The Minnesota Vikings. Here's Why They Didn't Call Back.
JC Tretter, NFLPA president and former Browns center, retires after nine seasons
JC Tretter Retires from NFL at 31; Former Packers, Browns Center Is NFLPA President, News, Scores, Highlights, Stats, and Rumors
On to the next chapter': Former Cleveland Browns center JC Tretter announces retirement
J.C. Tretter, National Football League, News, Scores, Highlights, Stats, and Rumors
Former Browns center, NFLPA president JC Tretter retires
Former Browns center JC Tretter announces retirement from NFL
JC Tretter's term as NFLPA president has included pandemic response and a divisive CBA vote - The Washington Post
JC Tretter Retires From NFL After Nine-Year Career - Sports Illustrated