The rookie quarterback left the game when driven to the ground by J.J. Watt. On the series prior to the injury, Mettenberger threw a 36-yard touchdown pass to Kendall Wright. Jake Locker replaced him and threw an interception on his first play.
Titans cornerback Johnathan Joseph injured his Achilles tendon in the third quarter and didn't return, but said after the game that he was OK. The Titans said wide receiver Justin Hunter has a lacerated spleen and will spend the night in a Houston hospital.
Giants right tackle Geoff Schwartz, playing in place of starter Justin Pugh, injured his left ankle and left on a cart against Jacksonville. His replacement, James Brewer, also left with a concussion. Running back Rashad Jennings went down with an ankle injury.
Coach Tom Coughlin said X-rays were negative on Schwartz's ankle, but he does have tendon damage. Giants linebacker Terrell Manning (ankle) and defensive end Robert Ayers (pectoral) also left the game. Jaguars defensive end Andre Branch reinjured a groin muscle that kept him out the previous four games.
The Browns issued the update four hours after the game Sunday. It's unclear when Austin was hurt in a game he had seven catches for a team-leading 86 yards.
Packers cornerback Sam Shields left the game against New England because of a concussion. He got hurt early in the second quarter on a play in which Patriots running back Brandon Bolden gained 12 yards.
Shields, who was not in on the tackle, stayed down for a few moments on one knee before getting up briefly. Shields went down again before the next play, then jogged off the field accompanied by trainers.
Rams guard Rodger Saffold aggravated a nagging left shoulder injury in the second half and did not return, but expects to play next week at Washington. Raiders tight end Brian Leonhardt (concussion) was hurt on a kickoff return in the first quarter and did not return. Offensive lineman Menelik Watson (ankle) was sidelined in the second quarter.
In other injury news:
-Baltimore wide receiver Marlon Brown landed hard on his back after making a first-down catch in the first quarter and left with a concussion against San Diego. Chargers center Chris Watt took a hit on his calf in the third quarter and did not return.
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