On Nov 28, 2008 Plaxico Burress shot himself in the leg in a NYC nightclub, at the time the Giants were defending SB champs and were 11-1, the class of the NFL. After the shooting the Giants went 2-3 and lost to the Eagles in the playoffs. Had Burress not shot himself the Giants would have finished much stronger and possibly made a deep run into the playoffs, who knows.
The following year Hakeem Nicks was choosen in the first round, a fantastic player, but if Burress was not in jail I'm not sure he would have been the pick