Per rotoworld:

Santana Moss (hamstring, questionable) was unable to practice for a fourth straight day on Saturday.
Moss did run some and said he “felt better,” but still can’t make cuts and is a very shaky bet to play Monday night. “We’re going to do it again (Sunday), see how he feels and then we’ll just make a game-time decision,” coach Jim Zorn said. James Thrash will start if Moss is out against Pittsburgh, with Devin Thomas moving up to the third receiver. Because the Skins are on a bye in Week 10, they could deactivate Moss to get him two full weeks to heal.

I will watch this carefully tomorrow but as the matchup was already shaky, you may want to just go another way.