According to PFW Patriots correspondent Ian Rapoport of the Boston Herald, Tom Brady aggravated the left shoulder sprain that he suffered earlier in the season on Justin Tuck's sack with 6:12 left in the third quarter of Super Bowl XLVI.
It is not believed that Brady was injured seriously but he certainly had to deal with quite a lot of pain after the sack.
His stats before and after the sack indicate that Brady wasn't the same player after Tuck drove his left shoulder into the ground. Before the sack, Brady was 20-of-24 passing for 201 yards with two touchdowns, including a Super Bowl-record 16 completions in a row. After the sack, he was 7-of-17 passing for 75 yards and one interception.
The Patriots led 17-12 when the hit occurred. They did not score again.
Patriots backup QB Brian Hoyer, who warmed up briefly after the sack but remained on the sideline as Brady continued to play, told Rapoport, "I don't know if I'll ever meet someone as tough as he is."