Tom Brady left the New England Patriots’ 17-10 win over the Kansas City Chiefs Sunday after his leg bent backwards during a passing play. Brady was able to walk off the field, but he didn’t return. It’s unclear at this point how bad the injury is.

Matt Cassel filled in well for Brady, throwing for 152 yards on 13 of 18 passing and a touchdown. Much like last year, Laurence Maroney split carries with Sammy Morris. Both backs got 10 carries as Morris rushed for 53 and Maroney 51, respectively. Randy Moss had 116 receiving yards on six receptions and hooked up with Brady for a first quarter touchdown.

The Chiefs also lost their starting quarterback after Brodie Croyle suffered a separated shoulder. Damon Huard finished the game and will likely start next week. KC gave the Pats everything they could handle without Brady, but dropped passes plagued the team all game. Larry Johnson rushed for 74 yards on 22 carries, but more importantly he looked healthy. I realize Brady didn’t play the entire game, but the Chiefs might not be as bad as people think this season based on their performance Sunday.

UPDATE: Michael Silver from Yahoo! Sports is reporting that Tom Brady may be out for the season with a torn ACL in his right knee. We’ll see if these reports are confirmed.