Gruden said Reed didn't practice Wednesday and will be evaluated on a ''week-to-week basis.''
Reed pulled his left hamstring on a 4-yard reception late in the first quarter of the season-opening 17-6 loss to the Houston Texans.
Niles Paul and Logan Paulsen would get extra playing time in Reed's spot.
Among other injury updates Wednesday, linebacker Brian Orakpo was limited in practice with a sprained right ankle, and left tackle Trent Williams was limited with a shoulder injury.
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