St. Louis, which went unbeaten in eight straight (7-0-1) to start December, has gone 2-4-2 in its last eight games, including Saturday's 3-1 home loss to San Jose.
Scott Mellanby scored the lone goal for the Blues, who have dropped two of three at home after losing just once in their first 16 games at the Savvis Center.
"I thought tonight was clearly a lack of effort," St. Louis coach Joel Quenneville said. "Just getting outworked, outhustled and that's basically it."
St. Louis goalie Chris Osgood returned to action Saturday after missing two games with a bruised right knee. He stopped 30 shots, but dropped to 1-2-2 in his last five starts.
Defenseman Barret Jackman also returned to the lineup for the Blues after missing 17 games because of a strained shoulder.
The Wild finished December on a nine-game unbeaten streak, but are 0-2 in 2003, including a 3-1 loss at Colorado on Sunday.
Jason Wiemer scored and Manny Fernandez made 26 saves for Minnesota, which had its franchise-record road unbeaten streak snapped at seven and remained winless in its last six games overall (0-2-4-0).
Minnesota has scored two goals or fewer in each of its last five games.