Steelers quarterback Byron Leftwich has a sprained medial collateral ligament in his left knee and he will miss two to four weeks with the injury, a source told the Post-Gazette today.

Leftwich, the presumed starter during Ben Roethlisberger's four-game suspension, was injured during the second quarter of Thursday night's preseason game against the Carolina Panthers at Heinz Field.

The Steelers have two other quarterbacks on their roster, veteran Charlie Batch and third-year player Dennis Dixon.

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