(Reuters) - The Pittsburgh Steelers' playoff hopes received a boost as starting quarterback Ben Roethlisberger was cleared to play after missing three games due to injuries, the National Football League team said on Thursday.

Roethlisberger, who has steered the Steelers to three Super Bowl appearances and two titles, will start Sunday against the San Diego Chargers after missing the last three games with shoulder and rib injuries.

"He has been above the line in all areas," said Steelers head coach Mike Tomlin. "Really, the only question we can't answer is taking a hit. Obviously that will be answered in the stadium on Sunday."

The Steelers (7-5) went 1-2 with Roethlisberger on the sidelines and need a strong finish over the last four regular season games to secure a wildcard berth in the playoffs.

Pittsburgh are two games behind the AFC North-leading Baltimore Ravens and tied with division rival Cincinnati Bengals in the wildcard race. The AFC South Indianapolis Colts (8-4) have the inside track for one of the wildcard berths.

(Reporting by Larry Fine in New York; Editing by Frank Pingue)