Steelers' Dixon needs knee surgery

Steelers quarterback Dennis Dixon will have left knee surgery Wednesday and is out indefinitely, meaning Byron Leftwich or Charlie Batch will start Sunday at Tampa Bay.

Dixon was hurt in the first half of a 19-11 victory at Tennessee on Sunday, with Batch playing most of the final three quarters - his most extensive game action since 2007. Leftwich, expected to start during Ben Roethlisberger's four-game suspension, sat out the first two games with a sprained left knee from the final preseason game.

Dixon's injury turned out to be more serious than suspected on Sunday, when coach Mike Tomlin said the third-year quarterback could have re-entered the game late to hand the ball off if necessary.

Tomlin does not expect Leftwich to be bothered by his injury this week in practice, but how well he responds may determine if he is ready to start.

Batch was the No. 4 quarterback during voluntary workouts and training camp and received almost no work with the starters before playing against the Titans.

Still, Tomlin said Batch is currently in the lead because he is the lone quarterback who has proven he' healthy. The Steelers (2-0) don't practice again until Wednesday.

''You've got to say Charlie's in the pole position because he's got a clean bill of health,'' Tomlin said Tuesday.

The Steelers traded with Tampa Bay to reacquire Leftwich immediately after Roethlisberger was suspended in April for violating the NFL personal conduct policy.

Leftwich was the backup when the Steelers won the Super Bowl two seasons ago, has an extensive knowledge of the playbook and very well could start against his former team if he can prove to Tomlin and the medical staff his knee is fine.

Leftwich throws the deep pass better than Batch, and starting him increases the chances of involving deep threat receiver Mike Wallace more extensively in an offense that has yet to score a touchdown in regulation.

The Steelers beat Atlanta 15-9 on Rashard Mendenhall's 50-yard touchdown run in overtime, and their only scoring in Tennessee came on four field goals by Jeff Reed and an Antonio Brown kickoff return.

The Steelers also may be without right guard Trai Essex (ankle) against Tampa Bay (2-0). If he can't start, undrafted free agent Doug Legursky would start.

Nose tackle Casey Hampton, held out of the Tennessee game with a hamstring injury, could be ready to play.