Oregon State quarterback Sean Mannion to have knee surgery, out indefinitely

Oregon State quarterback Sean Mannion will have surgery and will be out for Saturday's game against BYU. (Christian Petersen/Getty Images) Oregon State

Oregon State quarterback Sean Mannion will have surgery and will be out for Saturday's game against BYU. (Christian Petersen/Getty Images)

Oregon State quarterback Sean Mannion will have surgery on his knee, head coach Mike Riley announced Monday and is out indefinitely, reports the Oregonian.

Mannion, a sophomore, has completed 63 percent of his throws for 1,350 yards with seven touchdowns and four interceptions this season for the tenth-ranked Beavers.

Oregon State plays at BYU this Saturday. Junior Cody Vaz is next on the Oregon State depth chart at quarterback.  Vaz has not played since 2010, when he completed 6 of 17 passes for 48 yards.