It's been said over and over by sports analysts across the nation: any good team needs a good quarterback to compete.
Of course, this golden rule has been broken a few times: who quarterbacked the 1985 Chicago Bears? The 2000 Baltimore Ravens? The 2002 Tampa Bay Buccaneers?
Jim McMahon, Trent Dilfer, and Brad Johnson, for anyone keeping track.
But those guys would have been no more than a back-up on most other teams in the league those years. They didn't win games, but they didn't lose them either.
On the other hand, some teams have a logjam of talent at the quarterback position, and could field a viable option for a second quarterback should their starter go down.
Here are some of the back-ups who look like viable starters in the NFL.