Matt Cassel will be the starting quarterback for the Kansas City Chiefs on Thursday night against the San Diego Chargers.

Brady Quinn has been ruled out for Thursday's game after leaving this past Sunday's loss to the Oakland Raiders with a head injury. Chiefs coach Romeo Crennel told reporters that Quinn is being evaluated for a concussion.

Crennel decided to bench Cassel last week and promote Quinn to the starting role.

In six games this season, Cassel has thrown for 1,368 yards with six touchdowns and 10 interceptions.