The Blues' losing streak is now at four games, after falling to the Washington Capitals 4-1 Wednesday night at Scottrade Center.
Nicklas Backstrom had two third-period goals, including an empty-netter, as the Capitals ended an eight-game losing streak in St. Louis, dating to the 1996-97 season.
Despite registering 38 shots on goal, tying their third-highest total of the season, the Blues mustered only one goal from Alex Steen in the second period.
The club has now lost nine of their last 12 games and the four straight losses marks the longest string of the season in games decided in regulation.
The Blues opened the home schedule with a record of 8-0-1, but they have now dropped their last two games at Scottrade Center in regulation.
The Blues will be off until Saturday when it travels to Western Canada for a two-game road trip to Edmonton and Vancouver.
Nicklas Backstrom gets an empty-netter, his second goal of the game, with 35 seconds left in regulation to close out this game.
Capitals 4, Blues 1 ... with 30 seconds left.
Blues are on the power play, trailing 3-1, with under five minutes to play in regulation.
Washington's Jeff Schultz was called for high-sticking, putting the Blues on their fourth power play of the game. They are 0-for-3.
Capitals 3, Blues 1 ... with 4:45 left in regulation.
Brad Boyes had a chance to pull the Blues to within 3-2, but his point-blank shot hit the mask of Caps goalie Semyon Varlamov with 11:07 remaining.
Capitals 3, Blues 1 ... with 7:52 left in regulation.
Washington has increased its lead on Nicklas Backstrom's 10th goal of the season with 12:54 to play in the third period.
Backstrom jumped on a rebound and ripped a shot past Blues goalie Jaroslav Halak.
Capitals 3, Blues 1 ... with 11:40 left in regulation.
Andy McDonald put a shot on net, and as Washington goalie Semyon Varlamov was making the save, the goal net was pushed over by the Caps' Matt Hendricks, falling on top of Varlamov.
The distraction made the save a little more difficult, but after a review, it was ruled that the puck did not cross the goal line.
Capitals 2, Blues 1 ... with 13 minutes left in regulation.