New England Patriots quarterback Tom Brady played during the 2013 season with ligament damage in his throwing hand, according to Albert Breer of NFL Network.
The 36-year-old is believed to have sustained the injury in October, but bravely played through the pain barrier.
Brady, despite carrying the injury, still amassed 4,343 yards passing, 25 touchdowns and 11 interceptions, earning Pro Bowl honours.
Breer, meanwhile, added that Brady's injury has now healed - although questions might be raised as to why the Patriots allowed him to play with the injury.
The team stayed tight-lipped over rumours that he was injured a couple of months ago, when cameras spotted his hand looking swollen.
However, it is currently unclear whether the experienced two-time AP NFL MVP will be fit to participate in the Pro Bowl.
In Sunday's AFC Championship clash against the Denver Broncos on Sunday, Brady completed 24 of his 38 passes - and weighed in with one touchdown in the closing stages.