New England Patriots quarterback Tom Brady has fallen behind in his recovery efforts from knee surgery and could risk missing next season if another operation is needed, NBCSports.com has reported.

Brady, who underwent surgery Oct. 6 after tearing the ACL and MCL ligaments in his left knee in the first quarter of the team's first game of the season, had subsequent operations on the knee after it became infected.

That infection resulted in a buildup of scar tissue, which may require surgery on the knee, the Web site reported, citing an anonymous NFL source.

The scar tissue also has affected Brady's ability to begin fully rehabilitating his leg, the report said, and the repaired ligaments remain loose. Another surgery also could be needed for that condition, the Web site reported.