NORMAN, Okla. — Defensive end John Williams, a former starter who received a sixth year of eligibility from the NCAA, may not return to play his final season for No. 4 Oklahoma.

"Right now, John's just mentally having a hard time staying with it, and right now we don't anticipate him rejoining the team," Sooners coach Bob Stoops said today after practice.

Williams started three games for Oklahoma last season before tearing his left Achilles' tendon and missing the rest of the season. He was granted a waiver for a sixth season of eligibility in January because he had missed all but one game in 2005 after sustaining a season-ending knee injury in the opener against TCU.

"In the end, you've got to want to play. You've got to want to do the things necessary to play and play well," Stoops said. "It's unfortunate but in the end we're going to play this Saturday, so we're going to get ready to play."

Jeremy Beal, who replaced Williams after his injury last season, started against Chattanooga in Oklahoma's 57-2 season-opening win this weekend opposite preseason Big 12 defensive player of the year Auston English.

Oklahoma hosts Cincinnati on Saturday.