The NFL is investigating whether the Buffalo Bills have violated any league policies by failing to list defensive end Mario Williams on the injury report, ESPN has reported. Williams has grumbled about a sore left wrist for a few weeks and has worn a brace in plain view but he has yet to appear on an injury report this season. The issue is whether Williams should be listed or not. He has participated fully in every practice. That said, the NFL wants teams to identify injuries to reduce the chance of people trading inside information for gambling purposes. "All I do is I go out and I practice," Williams said. "I brace it up, do whatever I need to do to practice, and I play in the game. Now, I don't report anything. I don't know all the odds and ends about [the injury report]. I don't know if you go through practice if you report that or not. The players don't control that. "I didn't even know if I was on the injury report or not. I don't check injury reports. That's not what I do." Source: The Redzone