Backstrom was coming off consecutive shutouts of Edmonton, but the Blues broke Minnesota's franchise-record scoreless streak at 169 minutes, 20 seconds when Peter Sejna beat the Finnish goalie between the pads with a shallow angle shot in the second period.
It was an impressive offensive display from the Wild, who rested leading scorers Brian Rolston and Pavol Demitra as they prepare for the second postseason appearance in the franchise's history.
Things seem to be coming together at just the right time for Minnesota, which had a franchise-record, nine-game winning streak last month, but had scuffled a bit after the run was broken on March 27.
But the Wild have won three in a row heading into the postseason and have exhibited many of the elements needed for a deep run -- strong goaltending, tight defense and balanced scoring.
"I think we're ready," Lemaire said.
It will be another postseason without the Blues, who missed the playoffs for the second straight year after a remarkable run of 25 straight appearances. A wretched start to the season -- 7-19-6 -- is to blame, but optimism surrounds this young club.
The Blues finished the season strong under new coach Andy Murray, going 27-18-9 with youngsters like Lee Stempniak and Jay McClement stepping in after veterans Keith Tkachuk and Bill Guerin were traded. A win on Saturday would have allowed the Blues to finish above .500.
"If you look at the situation they were in in December with 18 points, we played pretty hard for a long period of time and set a standard for the way we hope to start the year next year," Murray said. "In my opinion, we did end the season on a high note. The people of St. Louis came to respect how hard we worked, and we've laid a foundation here now."
Their situation could be helped further if a few of their draft picks -- No. 1 overall pick Erik Johnson and T.J. Oshie leave college early and sign with the Blues.
St. Louis will also benefit from the return of goaltender Manny Legace, who played well enough this season to earn a two-year contract extension but missed the last 21 games of the season with an injured right knee.
The Blues could have used Legace against the Wild, who knocked starter Jason Bacashihua out of the game with two goals on eight shots in the first period.
Murray went with Sanford to start the second period, and he made a couple of impressive saves the rest of the way, but allowed three goals on 23 shots to the surging Wild.
"We've played some solid hockey lately," Bouchard said. "Confidence-wise, we're there. Now we have a few days to get ready for the Ducks."
Walz's goal was his first in 30 games. ... Former Minnesota Vikings player and Hall of Fame quarterback Warren Moon attended the game. He got a warm ovation upon receiving a Wild sweater with his No. 1 on it in the second period. ... Murray has Minnesota roots from his one-year stint coaching prep power Shattuck-St. Mary's in Faribault in 1998-99.
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Arena: Xcel Energy Center Location: Saint Paul, Minnesota
Referees: Stephane Auger, Tom Kowal Linesmen: Don Henderson, Mark Wheler