The NFL's best Plan B's: Ranking top 10 backup quarterbacks

NFL teams start a combined 22 offensive and defensive players in any given week. Sure, that starting lineup is important, but those 22 are hardly the only ones who can play a pivotal role in deciding who wins and who loses on Sundays.

NFL defenses play two-thirds of their snaps (conservatively) with five defensive backs on the field; we call it "nickel." That extra defensive back? He may as well be a starter when factoring in overall impact and contributions. (Think about just how much slot corner Aaron Colvin meant to the Jaguars in 2017; enough that he earned a contract for $9 million a year this offseason from Houston.)

A backup quarterback might not play at all in a given year -- that's the best-case scenario for an NFL team -- but still has incredible value. (Nick Foles, anybody?) As Philly has shown, a capable fill-in quarterback is a pivotal ingredient for a championship-caliber team. And any roster, really.

With that in mind, let's run down the NFL's top 10 backup quarterbacks: