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Yes, I know Reich isn't as good as other players I could put on this list, but this is a list of the best backups, not the best players who happened not to start.
In terms of career-long backups, few can match the resumé of Reich.
On several occasions he relieved an injured Jim Kelly to lead the Bills to important victories, but none meant as much Buffalo's wild-card playoff win over the Oilers in 1993.
Why does that win mean so much? Because it was the greatest comeback in NFL playoff history. The Bills were down 28-3 at halftime, but used a 35-3 second-half run to send the game to overtime and eventually win.
The irony here is that Reich also engineered the biggest comeback in college football history, a 31-point comeback for his Maryland Terrapins against the University of Miami.
Maybe Reich never became a star somewhere else, but that doesn't mean he wasn't a great backup, and that's what this list is about.