Four playoff teams overcame long odds this season

Each of the divisional playoff games features a team that appeared to have little chance of playing this weekend at some point this season.

The Baltimore Ravens were coming off a 5-11 season with a rookie head coach and a rookie quarterback who was forced into the starting lineup because two players ahead of him were unavailable.

The Arizona Cardinals limped into the playoffs having lost four of their last six games and were underdogs in the wild-card round in their own stadium against the Atlanta Falcons.

At the quarter mark of the season, the Philadelphia Eagles were in last place in the NFC East. They sneaked into the playoffs only because the Bears bungled their chance in Houston.

And the San Diego Chargers were 4-8 at one point and only made the playoffs by the ineptitude of the Denver Broncos.

Here is a look at how each of these improbable champions might fare this week.

Ravens at Titans

Key to the game: Whoever turns the ball over more probably will lose.

The Ravens led the NFL in takeaways and free safety Ed Reed is the league's leading interceptor. Baltimore intercepted Titans quarterback Kerry Collins twice the first time they met.

Ravens quarterback Joe Flacco is only a rookie, so he could be susceptible to turning the ball over in a game of this magnitude. Flacco, however, was a good caretaker in his first playoff game a week ago, and he has thrown only five interceptions in his last dozen games.

It could be a different story against the Tennessee defense, however. Between them, Titans defensive backs Michael Griffin Cortland Finnegan and Chris Hope have 16 interceptions.

X factor: Titans inexperienced backup center Leroy Harris will have to get the rest of the Titans blockers lined up in the proper protections against one of the most complex and aggressive defensive fronts in football.

The pick: Ravens 19, Titans 17.

Cardinals at Panthers

Key to the game: Everyone expects Carolina will run the ball more efficiently than the Cardinals. But if the Cardinals are going to have a chance, they must prevent DeAngelo Williams and Jonathan Stewart from going crazy, and they will need at least a semblance of a run game themselves.