Mike Tanier

Even the best teams are just one hit away from a quarterback emergency.

The Packers learned that lesson on Sunday, when Aaron Rodgers suffered a concussion and Matt Flynn couldn’t muster more than a field goal against the Lions. During a stretch run or in the playoffs, losing a quarterback for half of a game can ruin a season — unless the backup delivers.

Some of the league's strongest teams, like the Packers, have clay feet when it comes to quarterback depth. Meanwhile, some second-tier contenders have proven ex-starters or talented prospects waiting on the bench. Some teams are built to withstand a quarterback crisis because they rely on the running game or defense. Other teams live and die on the fortunes of their quarterback.

With the playoffs approach, I ranked all of the contenders on how well prepared they are to lose their starting quarterback for a game or two. There is a lot of speculation mixed with the stats — some of these quarterbacks haven’t played a meaningful snap in years, if at all — but overall, it is clear that some postseason-bound teams have much better contingency plans than others.

1. Jets
Mark Brunell looked like a creaky old man in his Week 17 relief appearance for the Saints last year, throwing for just 102 yards and an interception in a meaningless loss. But the Jets offense is a geezer pleaser: they have a great offensive line, an effective running game, and lots of play-action passes, plus a defense that keeps most games close. With all of that heavy steel around him, Brunell can steer the Jets to a win or two, his directional blinking the whole time.

2. Steelers
Two journeyman backups are better than one. Byron Leftwich is a poor man’s Ben Roethlisberger. He’s a slow worker in the pocket who takes too many sacks, but he has a strong arm and a willingness to gamble for big plays. Leftwich also comes pre-injured for your convenience — he has been practicing with a knee brace, so the Steelers have to be ready for Plan C. Charlie Batch held down the fort during the Ben Roethlisberger suspension with wins over the Titans and Buccaneers. He’s rickety, but he has been in Pittsburgh longer than Iron City beer, so he knows his role.

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3. Ravens
A veteran with 95 career starts, Marc Bulger lacks Joe Flacco’s bombing ability, but his quick release could add a short passing dimension to the Ravens offense if he is called upon. Bulger completed 65.6 percent of his passes in the preseason, so he knows the system. At 33, he isn’t as far over the hill as some of the other backups on this list.

4. Falcons
Chris Redman was written off as a joke when Bobby Petrino signed him to the Falcons in 2007; Redman had drifted into the Arena Football League, and it appeared that Petrino was just doing his old Louisville University quarterback a favor. But Redman stuck, and last year he was solid in losses to two good teams: the Eagles (23-of-44, 235 yards, 1 TD, 2 INT) and the Saints (23-of-34, 303 yards, 1 TD, 1 INT). Redman is a system quarterback, and the Falcons are so solid overall that Redman can win games while sticking with the system.

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5. Eagles
Kevin Kolb is one of two opening day starters on this list, and the only one still with his original team. Kolb has put up respectable numbers this season (1,035 yards, 63.4 percent completions, 6 TDs, 4 interceptions) and led the Eagles to wins over the 49ers and Falcons. He doesn’t provide Vick's "wow" factor, but Kolb has been in the system for years and has proven he can get the job done in spot starts.

6. Chargers
With just 44 attempts in four years, Billy Volek has become an unknown commodity. Volek’s 2010 preseason stats were awful: no touchdowns, 4 interceptions, a 50.7 percent completion rate. Preseason stats are worthless, but you have to wonder about a 34-year old system veteran who can’t march straight down the field in August against a bunch of rookies. Volek played well in rest-the-starters action last season, throwing for 216 yards in Week 17 against the Redskins, so we have to assume he still has something left.

7. Patriots
Tom Brady’s backups are usually mystery men with uninspiring college records, just like Brady. Brian Hoyer has knelt to end blowouts and seen some empty-the-bench action, and he doesn’t look like anything special. But keep in mind that he had to battle through a gauntlet of contenders (Matt Gutierrez, Andrew Walter, Kevin O’Connell) to win a backup job in 2009, and that he’s seen a great deal of preseason action, some of it with the first-team offense. The problem with Hoyer is that he is not Brady: with their timing-and-reads based offense, the Patriots are much more reliant on Brady than the Jets are on Sanchez or the Steelers on Roethlisberger.