Ryan O’Reilly scored early in the third period to lift the Blues to a 4-3 win over the Jets in Winnipeg.
Oskar Sundqvist scored twice and Patrick Maroon added a goal for St. Louis, while Jordan Binnington stopped 26 of 29 shots to pick up the win.
Winnipeg captain Blake Wheeler tied the game at one-all in the first, while Patrik Laine and Mark Scheifele each added power-play goals in the second.
Connor Hellebuyck stopped 28 of 32 shots in the loss.
The Blues hold a 2-0 series lead against the Jets as the series shifts to St. Louis.