FOXBOROUGH, Mass. (AP) -- New England quarterback Tom Brady left Sunday's game against Kansas City after being hit on the left leg, depriving the Patriots of the reigning NFL MVP.
The team said he had a knee injury and would not return.
The two-time Super Bowl MVP, who has started 128 consecutive games, went to the turf clutching his left knee midway through the first quarter when he was hit in the pocket by Chiefs safety Bernard Pollard. After being tended to on the field, he walked off, limping, between two trainers.
Brady, 31, went to the locker room and was not seen again on the sideline.
Brady was 7-for-11 for 76 yards before leaving, completing a 26-yard pass to Randy Moss on the play in which he was injured. Moss fumbled the ball away when he was tackled and; the Patriots forced Kansas City to punt, backup Matt Cassel took over at for New England.
Cassel took over at his 2 yard-line and, after two handoffs nearly netted the Chiefs a safety, completed his first pass to Moss for a 51-yard gain. Cassel, Brady's backup for the past three years, finished the 98-yard drive with a 10-yard touchdown pass to Moss that gave New England a 7-0 lead.
A former fourth-stringer who was the 199th overall selection in the 2000 draft, Brady himself took over at quarterback when longtime starter Drew Bledsoe sustained a life-threatening chest injury in a 2001 game against the New York Jets. Brady led the Patriots to their first NFL title that year, another in 2003 and another in 2004.
In the process, Brady has become one of the league's biggest stars and a crossover cover boy who has met the Pope and the president, dated actresses and supermodels and rewrote one of the NFL's most coveted records.
Last year, while leading New England to a 16-0 regular season, Brady set a record with 50 touchdown passes and improved his overall record as a starter to 100-27 - the best in the Super Bowl era. The Patriots blew a chance at an unprecedented 19-0 season and a fourth NFL title with a 17-14 loss in February's Super Bowl to the New York Giants.
Brady did not play in four exhibition games this summer - all of them Patriots losses - while trying to recover from a right foot injury.