CORVALLIS Â Just after climbing into the top 10 with a 4-0 start, the Oregon State Beavers have suffered a huge blow.
Quarterback Sean Mannion, who has helped lead OSU to the No. 10 spot in the NCAA Division I rankings, will be out for at least a month and possibly the season Â with a knee injury.
Mannion injured the meniscus in his left knee on a handoff in Saturday's 19-6 home win over Washington State. The injury happened on a routine handoff, but Mannion didn't feel it until his knee swelled up on Sunday morning.
The sophomore QB from Pleasanton, Calif., will undergo surgery on Tuesday. Depending on what is found during the operation, he could be out for about a month, or be lost for the rest of the year.
The Beavers' new starting quarterback for Saturday's game at BYU is redshirt junior Cody Vaz, with walk-on freshman Richie Harrington the backup. Harrington, 6-1, 225 pounds, is from Westlake Village, Calif.
Vaz, a 6-1, 195-pounder from Lodi, Calif., has appeared in five games, all in the 2010 season. He completed 6 of 17 passes for 48 yards, with no touchdowns and no interceptions.
In four games this season, Mannion has passed for 1,358 yards and seven touchdowns, completing 63.7 percent, with four interceptions in 107 attempts.