Thurman Thomas
The Bills lost four straight Super Bowls as they turned it into an art form. But Thomas gave everything in 1991 against the Giants. He managed to achieve lethal productivity even though the Bills underutilized him. Thomas set the standard for losing players with this heroic display (via Bleacher Report).

Thurman rushed for 135 yards and a touchdown on 15 carries. Everything he did was brilliant but the Bills failed to get over the line. This was agonizing for Thurman because he deserved more. It remains shocking that Thomas didn’t get a ring but he won the league’s MVP award. The running back was one of the best players of his generation.