Report: Broncos' Walton has ankle surgery

Denver Broncos center J.D. Walton underwent a second surgery on his left ankle Monday and will miss the start of the upcoming regular season, according to the Denver Post.

Sources told the newspaper that Walton had a follow-up procedure to repair existing hardware in the ankle, which he fractured and dislocated during a Week 4 rout of the Oakland Raiders on Sept. 30 of last season. The fourth-year pro was placed on injured reserve shortly afterward.

Walton is expected to be sidelined until late October or early November, though the possibility he could miss the entire season exists if any further complications arise.

The 26-year-old has served as the Broncos' regular center since entering the NFL as a third-round pick in 2010, starting a total of 36 games over that span.

The Post also reported that Walton's injury could prompt the Broncos to bring back veteran Dan Koppen, who took over as the team's center for the final 12 regular-season contests as well as Denver's loss to Baltimore in the AFC Divisional Playoffs. The 33-year-old Koppen is presently an unsigned free agent.