Jackson did not practice Friday, and coach Jay Gruden says, ''If he is not at full strength, then it will be a long shot for him to play.''
Jackson leads Washington with 942 yards receiving - nearly twice as many as anyone else on the team - and five touchdown catches.
Also questionable after missing practice Friday is linebacker Keenan Robinson, who has a knee injury.
The long list of injured Redskins (3-9) also includes defensive tackle Kedric Golston, who will be out Sunday with foot and back problems, and safety Brandon Meriweather, listed as doubtful because of a hurt toe.
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