NORMAN, Okla. -- Oklahoma starting nose tackle Jordan Phillips likely is out for the season with a back injury.

Stoops said during his weekly press conference that Phillips will undergo surgery on Tuesday. Stoops also said that linebacker Corey Nelson, who tore a pectoral muscle on Oct. 5 against TCU, also will have surgery Tuesday. Nelson already had been ruled out for the season.

Phillips, a 6-foot-6, 324-pound redshirt sophomore, didn't play against TCU or on Saturday against Texas due to back problems. He started the first four games for No. 18 Oklahoma and had been a pleasant surprise for the Sooners, recording seven tackles, including two for loss, and one sack.

Redshirt freshman Jordan Wade started against TCU and Texas in Phillips' absence.