D.J. King scored his first career goal, and Radek Dvorak and Barret Jackman also scored for the Blues, who have won three of their past four. Daniel Carcillo and Jeremy Roenick scored for the Coyotes, who have lost 13 of their past 15 games. Weight gave St. Louis a 1-0 lead 3:12 into the game when he pounced on a long rebound at the bottom of the right faceoff circle and fired the puck over goalie Curtis Joseph.
Cajanek was credited with a goal at 6:53 of the first period when his pass from the left wing was deflected into the net by Coyotes defenceman Zbynek Michalek.
Carcillo cut the Blues lead to 2-1 when he redirected Keith Ballard's shot from the point past Jason Bacashihua. Jackman fired a shot from the top of the right circle over Joseph's glove to put St. Louis ahead 3-1.
Dvorak made it 4-1 at 9:12 when he tucked a shot just under the crossbar. Roenick pulled the Coyotes within 4-2 at 14:25 on a redirection off a Shane Doan shot from the high slot, but King added his goal a little more than two minutes later from the bottom of the left circle.
Joseph, making his seventh start in nine games in pursuit of Terry Sawchuk on the career wins list, stopped 17 of 22 shots in the first two periods before he was replaced by Mikael Tellqvist at the start of the third.
Notes: Weight has scored 10 of his 16 goals since the trade deadline. ... Doan was playing in his 800th career game, all with the Winnipeg-Phoenix franchise. ... King, who has played in 25 games for St. Louis, had recorded his first career point on Monday at Dallas. ... Joseph, who has lost his past four starts, has been pulled twice in his past three starts. Joseph earned his 444th career win March 22 against Anaheim to move within three victories of Sawchuk for fourth place.