The Washington Redskins dominated the St. Louis Rams on defense Sunday, limiting them to just 172 yards of total offense, sacking the quarterback seven times and bottling up running back Steven Jackson for only 45 yards on 17 carries.

“Obviously, defensively, I think we played our best football game since I’ve been here,” said Coach Mike Shanahan. “ I thought our run support was excellent and the pass defense was excellent. We kept them off-balance with our own third down situations and we got after the quarterback.”

Through four games, the Redskins’ defense ranks fifth in the NFL and second in the NFC, limiting opponents to 296.5 yards per game (212 passing, 84.5 rushing). Washington has surrendered the third-fewest number of points this season (15.8 per game), and on third down, it ranks third, allowing foes just a 26 percent success rate.

A year after struggling to generate sacks – the Redskins ranked 31st with only 29 sacks in 2010 – Washington is tied for the league lead with 15. And the Redskins have forced a total of six turnovers (three interceptions, three fumbles), eighth in the league.

Shanahan’s message to his players has been to avoid getting caught up in early season success, and to look ahead to the next game rather than the accomplishments of the first four weeks.

“This is a game-by-game league,” the coach said. “We can talk next week and all you guys will be talking about is how poor a defense played and what’s wrong with our defense if we don’t play well. Our guys are smart enough to understand what happens in this league. … It takes one game for it to go the opposite way very quickly.”