QB Ben Roethlisberger's right shoulder injury has added a level of uncertainty to what appeared to be a clear AFC playoff picture.

For weeks, the Pittsburgh Steelers appeared to be among five 2011 AFC playoff teams -- Houston, Denver, New England and Baltimore being the others -- set to return to the playoffs. But the timing of Roethlisberger's injury couldn't be worse for the Steelers. They trail the Baltimore Ravens by a game in the AFC North, but the next three weeks give the Steelers the chance to climb back into the division race.

For now, the Steelers list Roethlisberger as questionable for Sunday's home game against the Ravens while they seek more information about his injury.

If Roethlisberger misses any one of the next three games or all three, the Steelers could be forced to lower their hopes of being a division winner to just hanging on to a wild-card spot. The possibility of missing the playoffs also creeps into the equation.

One of the reasons the Ravens have the one-game lead over the Steelers is because Baltimore has beaten the 2-7 Cleveland Browns twice. The Steelers haven't yet played a Browns team they have dominated through the years. The Steelers were counting on sweeping the Browns.

Since Sunday night's Ravens game is in Pittsburgh, the Steelers felt optimistic about their chances. Coach Mike Tomlin didn't show any panic at his Tuesday news conference, but the Steelers' offense drops off when backup Byron Leftwich plays instead of from Roethlisberger. Leftwich's long, slow release leaves him vulnerable to sacks, injuries and incompletions.

The sad overall state of the AFC, though, still gives the Steelers a chance to earn a wild-card berth if they have trouble in their two games with the Ravens over the next three weeks and their Nov. 25 game against the Cleveland Browns.

The Ravens already are 3-0 in divisional games. The Steelers beat the Cincinnati Bengals on the road, and five of their last seven games involve the AFC North.

If Roethlisberger misses Sunday's game against the Ravens and the Ravens win, the top four seeds will be taking shape in the AFC. The Houston Texans at 8-1 are running away with the AFC South. They lead the Indianapolis Colts by two games, and the Colts face a tough road trip to New England this week. The Patriots (6-3) lead the Miami Dolphins by two games in the AFC East. The Denver Broncos could open a three-game lead over the San Diego Chargers in the AFC West if they beat the Chargers at home Sunday.

That would leave the Colts and Steelers as the front-runners for two AFC wild-card spots. But Roethlisberger's injury gives hopes to three 4-5 teams that trail the Steelers (6-3) by two games -- the Dolphins, Chargers and Bengals.

The Chargers visit Pittsburgh Dec. 9. If Roethlisberger is out four games and the Steelers drop both games to the Ravens, the Chargers could bolster their wild-card chances if they fall out of the AFC West race. The Bengals play the Steelers in Heinz Field on Dec. 23 with some hope of catching them if the Roethlisberger injury lingers.

The Steelers also have a problem when it comes to tiebreakers. Their early-season success came at the expense of the NFC East. The Steelers were 3-0 against the NFC East, but they are 3-3 in AFC games. Two losses to the Ravens and any other AFC losses down the stretch would make it much tougher to make the playoffs.

For the Steelers to make it without Roethlisberger for any period of time, they will have to rely on their defense. In 2010, the Steelers pulled out a 3-1 record thanks to their defense when Roethlisberger opened the season with a suspension. One of those wins was against the Ravens.

It doesn't help that safety Troy Polamalu is doubtful for this week's Ravens game, but Steelers fans will be waving their Terrible Towels trying to beat their top rival.