Jack Dempsey, Associated Press
In this Nov. 17, 2011, photo, New York Jets' Joe McKnight (25) runs with the ball during an NFL football game against the Denver Broncos in Denver. A person with knowledge of the injury says running back/kickoff returner McKnight has a separated right shoulder. The person, who spoke on condition of anonymity because the team has not announced the injury, says McKnight was hurt in Sunday's loss to the Eagles, Dec. 18.

JERSEY CITY, N.J. — New York Jets running back/kick returner Joe McKnight has a separated right shoulder and his status for Saturday's game against the Giants was uncertain.

Coach Rex Ryan confirmed the injury Monday on his weekly radio appearance on 1050 ESPN Radio, adding that "we'll see" if McKnight can play.

It was not known when McKnight, who leads the NFL in kickoff return average, was injured in the Jets' 45-19 loss to the Philadelphia Eagles on Sunday. He played into the fourth quarter, but is also still healing from a hyperextended right elbow that sidelined him for a game.

McKnight, attending teammate Bart Scott's charity go-kart event at Pole Position Raceway on Monday night, said through a team spokesman that he preferred to not address the injury at that time because he was there with family for the event. His arm wasn't in a sling or appear noticeably hindered.

McKnight is the team's third-string running back, but as a kickoff returner he is averaging 32.3 yards a return, best in the league, and has a 107-yard touchdown. This is McKnight's second pro season.

Starting running back Shonn Greene injured his left pinkie during the game, and it was wrapped Monday night, but he said it was fine.