Week 3 is usually way too early in the season to talk about any particular game being a must-win, but a look at the Redskins’ schedule through Halloween is cause for reconsideration. Given the passing defense’s performance over the first two weeks (second-most passing yards allowed in the league), the prospect of facing quarterbacks like a rejuvenated Michael Vick, Aaron Rodgers, Peyton Manning, and Jay Cutler in a four-week span doesn’t inspire much hope — but hey, that fun starts next week. This weekend, the Redskins take to the road for the first time this season to face the winless St. Louis Rams, who are 3-31 over their last 34 games. The Redskins need not only to win this game, but to dominate a weak team that is surprisingly giving its opponents fits so far this year.