Oakland quarterback Terrelle Pryor left Monday's game during the fourth quarter with with a head injury that was later diagnosed as a concussion, according to Vic Tafur of the San Francisco Chronicle. The Raiders said Pryor was undergoing further evaluation.

Pryor was injured on Oakland's second-to-last drive. After the Raiders drove into Denver's red zone, Pryor scrambled on the second down play and was sandwiched between Bronco defenders. Pryor remained in the game, attempting two more pass attempts. Following the drive, Pryor was taken back into the locker room for further evaluation.

Oakland cornerback Tracy Porter also suffered a concussion. A teammate's knee hit Porter in the helmet while he was attempting to make a tackle.

The Broncos secondary took a hit during the game with safety Duke Ihenacho and cornerback Tony Carter leaving the game with ankle injuries. Carter injured his ankle during the first half while Ihenacho excited in the second half. Both play key roles for the Broncos. Denver is already thin in the secondary with Champ Bailey yet to make his 2013 debut. If Carter or Ihenacho are forced to miss time, the Broncos' depth could really be tested.

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