Doctors who have examined Brian Griese's left knee believe that the Tampa Bay quarterback has both a torn ACL and MCL, multiple team sources have told ESPN's Chris Mortensen. The Buccaneers have not yet made an announcement concerning the extent of the injuries. The injuries, however, are expected to keep Griese sidelined for the rest of the season. Coach Jon Gruden had said the knee injury could sideline the Tampa Bay quarterback for weeks or possibly the season. Gruden emphasized that the team had not received a firm diagnosis but raised the possibility that Griese, who has helped the Bucs to a 5-1 start, could be out for the season after being hurt during Sunday's 27-13 victory over Miami. "It is right now a twisted knee, a sprained knee. Whether it's more serious than that, we'll find out," Gruden said early Monday. "It could be a few weeks, it could be the end of the season. We don't know for sure. I'll just sit here and wait until I'm told the extent of this injury."