The Jets announced Saturday after the team's walkthrough that Lattimore has a head injury, but did not say when it occurred. New York held a full practice Friday at the London Irish RFC grounds.
Linebacker Trevor Reilly also has been upgraded from out to questionable for the game Sunday. Reilly missed the Jets' game against Philadelphia last Sunday with a badly infected finger.
Guard Willie Colon (knee), tight end Jeff Cumberland (concussion), wide receiver Chris Owusu (knee) and cornerback Darrin Walls (hamstring) remain out. Wide receiver Eric Decker (sprained knee) is a game-time decision.
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