The Dallas Cowboys are bringing in reinforcements on the offensive line after a couple of training camp setbacks at guard.
The Cowboys signed former TCU guard Jeff Olson and former UTEP tackle James Nelson, who went to high school near the team's camp facility in Oxnard, Calif. Dallas released injured defensive tackle Cameron Sheffield and cornerback Devin Smith on Thursday.
The additions of Olson and Nelson came after Kevin Kowalski sustained a knee bruise on Tuesday and Nate Livings didn't come out for Thursday's walkthrough because of knee soreness. Kowalski is expected to miss at least two weeks.
Even with Olson, the Cowboys have only five healthy guards heading into their preseason opener Sunday against Miami in Canton, Ohio.
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