TAMPA, Fla. — Tampa Bay Buccaneers leading rusher Earnest Graham will miss the rest of the season after injuring his right ankle during last week's victory over the Minnesota Vikings.

Graham limped off the field after his only carry against the Vikings. The Bucs said he hurt his ankle, but did not release specifics about the injury.

Fourth-year pro Noah Herron was signed to fill Graham's spot on the roster. He has appeared in 23 games with Green Bay and Pittsburgh, rushing for 273 and three touchdowns and catching 29 passes for 211 yards and two TDs.

With Graham out, Warrick Dunn moves into the featured tailback role. He will be backed up by Carnell "Cadillac" Williams, who hasn't played in a game since September 2007 because of a serious knee injury.

Williams was moved from the physically unable to perform list to the active roster last week.

The Bucs also placed rookie linebacker Geno Hayes (knee) on injured reserve and signed linebacker Matt McCoy, who played in three games for Tampa Bay before being released on Oct. 18.