Backup: Shaun Hill

Best-case scenario: Reggie Bush becomes the second option that Stafford has always needed, while also managing to reinvigorate the Lions' running game. Detroit's new, high-octane offense carries them to 10 wins and a trip to the playoffs.
Worst-case scenario: Stafford hangs onto Calvin Johnson and refuses to let go. Defenses regularly gang up on Megatron because they know that's all they need to do to put Detroit down. Led by this stagnant, predictable offense, Los Leones limp to a 6-10 season in a tough NFC North.