A rash of injuries to quarterbacks in Week 10 means four teams likely will have new starters behind center as they approach this weekend's games.
With three of the affected teams strongly in the playoff hunt and the other one likely fighting to save a coach's job, how these guys play in their spot (or longer) duty should have a significant impact on their squad's season. Here's a quick primer on what to expect.
Byron Leftwich, Pittsburgh Steelers
The 10-year veteran hasn't started a regular-season game since 2009 with the Tampa Bay Buccaneers. He showed his rust in relief of Roethlisberger on Monday night, completing seven of 14 passes for 73 yards. Leftwich is 1-1 in his career against the Baltimore Ravens, whom the Steelers host Sunday night, but hasn't faced the team since 2005 with the Jacksonville Jaguars. With Charlie Batch the only other quarterback on the Steelers roster, it's a good thing Leftwich can play hurt when he needs to.
Colin Kaepernick, San Francisco 49ers
Alex Smith's status for Monday night's game against the Chicago Bears is undetermined after he suffered a concussion against the St. Louis Rams, leaving the 2011 second-round pick in line to potentially make his first career start. The 6-5, 235-pound Kaepernick had been mostly used in running formations before taking over after Smith's injury, but he has been developed as a potential starter since arriving in the Bay Area. The Bears defense will be a tough potential foe, but Kaepernick's T-shirt seems to indicate he's confident he can handle it if Smith hasn't recovered in time.
Jason Campbell, Chicago Bears
If Jay Cutler misses time because of a concussion suffered against the Houston Texans, there's a good chance Bears fans won't take him as for granted as they do now. They have a backup with significant experience in the role, though, as Campbell is 31-39 in his career as a starter. He led to Oakland Raiders to a 4-2 start in 2011 before missing the rest of the season with a broken collarbone. Campbell threw on 22 of 34 plays after replacing Cutler on Sunday, so it appears that the team doesn't plan to limit its offense with him in the game.
Nick Foles, Philadelphia Eagles
Just when Michael Vick finally got off to a good start in a game, he was knocked out with a serious concussion, forcing the rookie from Arizona into the starter's job for the time being. It's probably not a bad thing that Philadelphia will get a good look at the third-round pick now, as they'll have a body of work to evaluate when making what looks to be a series of personnel decisions after the season. Foles fared so-so in relief duty against the Dallas Cowboys, but will need more help from Philly's banged-up offensive line to make much of a difference. He broke all of Drew Brees' high school passing records at Austin's Westlake High, so he's got that going for him. Though if he takes the kind of beating Vick has this season, we should probably prepare to see third-stringer Trent Edwards at some point, too.