The New England Patriots quarterback and twice Super Bowl MVP Tom Brady will miss the remainder of the season with an injury to his left knee.
Brady was hurt during the first quarter of yesterday's 17-10 season-opening victory over the Kansas City Chiefs when he was hit in a tackle.
The Patriots, who have won three NFL championships with Brady at the helm, were undefeated last season until the Super Bowl when they lost 17-14 to the New York Giants.
Brady was replaced against the Chiefs by Matt Cassell, a seldom-used quarterback who has not started a game since high school.
Cassell, 26, completed 13 of 18 passes for 152 yards and one touchdown. New England will visit the New York Jets and Brett Favre this weekend.