Tampa, FL (My Sportsbook) - Tampa Bay Buccaneers running back Earnest Graham is likely done for the season with a right ankle injury suffered in Sunday's 19-13 win over the Minnesota Vikings.

Bucs head coach Jon Gruden addressed the injury in a Monday press conference.

"Graham's ankle looks to be a serious injury and his status for the rest of the season is very much in question," Gruden said. "His season could be in jeopardy right now. I'm just very disappointed for our guy. He's done so much for us here. He's a key reason why we are where we are."

The five-year veteran was hurt on his first carry of the game and had to be helped to the sideline. After being attended to by trainers, he was taken to the locker room for further examination. He had also been nursing a knee injury in the week leading up to the game.

"He just landed awkwardly in a pile and it's unfortunate," Gruden added.

The injury means former first-round draft pick Carnell "Cadillac" Williams, who was activated off the physically unable to perform list early last week, will most likely see extended time at the running back position.

Williams has not played an NFL game since September 30, 2007 when he suffered a torn patellar tendon in a contest against Carolina. He returned to practice late last month after an arduous recovery and rehab.

To make room for Williams on the active roster, the Bucs released running back Michael Bennett last week. He was quickly claimed by the San Diego Chargers.

"I don't live in hindsight," Gruden said, addressing the sudden need for another back. "You've got an injury -- you've got to respond to it. We'll bring in some other backs that we like."

Graham and Warrick Dunn had split the running back duties to this point. Graham leads the team with 563 yards and four touchdowns, while Dunn has chipped in 476 yards and one score. Both are averaging more than four yards per carry.