The duo's long day ended with big third-period efforts from both veterans and another gritty win for their surging new team.
Los Angeles acquired Lecavalier and Schenn from the Flyers on Wednesday, and they barely had time to complete their physicals before coach Darryl Sutter put them in the lineup. Both played solidly against the Maple Leafs despite jet-lag and Lecavalier's rink rust.
''I've still got to learn the system, but for the first game, I felt good,'' Lecavalier said. ''I was afraid my legs wouldn't get going after the travel, but I felt good.''
Carter also scored in his return from a five-game injury absence for the Kings, who have won six of seven to open a 10-point lead over Arizona atop the Pacific Division.
Lecavalier set up Muzzin for the game's first goal with 17:07 to play, capping a solid effort in the 17-year NHL veteran's first game since Nov. 12. He also took faceoffs in the third period while centering the Kings' fourth line.
Lecavalier had been a constant healthy scratch with the Flyers. The former Richard Trophy winner had just one assist in seven games with Philadelphia this season before entering limbo, which ended with a trade and one more chance to win the Stanley Cup before he retires this summer.
''Both gave us quality minutes,'' Sutter said. ''I'm sure it's not easy. Give them credit. We wanted quality shifts out of them, and we got it.''
Schenn capped his effort with an enormous play in the final minute, poking a loose puck away from Jonathan Quick's net while Toronto had an extra attacker.
''It means a lot to get that opportunity at the end,'' Schenn said. ''I'm really honored to have that trust from the coaches.''
Quick made 25 saves to remain unbeaten since Dec. 22 for Los Angeles despite losing his bid for his third shutout in eight starts on Peter Holland's power-play goal midway through the third. Quick has won 13 of his last 15 starts, yielding just five goals in the past five.
''They're such a good team,'' Holland said of the Kings. ''They're big, they're fast, they're strong, and also playing them at home adds another element as well.''
James Reimer stopped 39 shots in his first start since Dec. 3 for the Maple Leafs, whose three-game winning streak ended in the middle stop of a three-game California trip.
Reimer missed all but one period of the past five weeks with a persistent groin injury. He had a busy night against the Kings' shot-heavy offense, but his teammates couldn't get an even-strength goal past Quick.
''I didn't feel I was as sharp as I would like to have felt, but I found a way to make saves,'' Reimer said. ''I've worked hard in practice, trying to stay as sharp as I can. They got a couple of good goals in the third, and that was enough for them.''
Toffoli turned his back shortly before the hit, which left him down on the ice for several moments. Sutter thought Polak deserved the major penalty, while Toronto coach Mike Babcock thought Polak tripped over Toffoli when the Kings forward turned.
Referee Kelly Sutherland also left the game late in the first period after Muzzin's shoulder hit him in the head. Both Sutherland and Toffoli returned for the scoreless second period.
Carter, who had been out since Dec. 28 with an upper-body injury, got his 12th goal on a slick cross-ice pass from Marian Gaborik.
NOTES: Los Angeles avenged a 5-0 loss in Toronto on Dec. 19. ... The Kings opened a four-game homestand after playing just two games at Staples Center in the previous 4 1/2 weeks. ... C Nick Shore and D Jamie McBain were scratched in favor of the Kings' new arrivals.