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AP Dallas Cowboys running back Phillip Tanner (34) heads for the endzone after losing his helmet on an attempted tackle in the second half of a preseason - Photo

Dallas Cowboys running back Phillip Tanner (34) heads for the endzone after losing his helmet on an attempted tackle in the second half of a preseason

Monday August 22, 04:09 AM
Dallas Cowboys running back Phillip Tanner (34) heads for the endzone after losing his helmet on an attempted tackle in the second half of a preseason NFL football game against the San Diego Chargers Sunday, Aug. 21, 2011, in Arlington, Texas. Officials ruled that the ball was dead once Tanner lost his helmet and therefore the touchdown was nullified. The Chargers won 20-7. (AP Photo/LM Otero)