Fine, John Moffitt. Be that way.

The Broncos placed their backup offensive lineman on the reserve/left squad list Tuesday when Moffitt failed to report to the team Monday after their bye week. The Broncos have a five-day exemption before they either officially remove Moffitt from their roster, or bring him back.

Moffitt's departure had convenient timing as the Broncos activated center J.D. Walton from the physically unable to perform list to their 53-man roster by the 2 p.m. Tuesday deadline.

Moffitt told the team he was retiring from football, but a source close to him said the third-year NFL lineman from the University of Wisconsin is doing some soul searching amid frustration at his lack of playing time.

Moffitt, 27, had started 15 games at guard for the Seattle Seahawks in 2011-12. He was inactive in six of eight games since the Broncos acquired him from Seattle in a late August trade for defensive tackle Sealver Siliga.

On Tuesday, Moffitt told 102.3 ESPN he was thinking about his long-term health, saying, "Scientists do know that hits to the head do deteriorate your brain," and that wasn't a risk he was willing to take any longer.