ARLINGTON, Texas (AP) — Pittsburgh Steelers guard David DeCastro will make his regular season debut Sunday against the Dallas Cowboys.

The Cowboys will be without their 2012 first-round pick, cornerback Morris Claiborne.

DeCastro won the job at right guard in training camp after Pittsburgh drafted him 24th, but he injured his left knee in a preseason game. He played special teams the past two weeks. Ramon Foster is moving over to the injured Willie Colon’s spot at left guard to make room for DeCastro.

Claiborne, the No. 6 pick in the draft, is inactive after sustaining a concussion in last week’s win at Cincinnati. Mike Jenkins will start in his spot.

Cowboys guard Nate Livings is active after being listed as questionable with a concussion.

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