Morrow scored twice, Lehtonen stopped 34 shots to rebound from a poor performance in his previous start and the Stars beat Edmonton 3-1 on Wednesday night in the final game before the All-Star break for both teams.
Adam Burish added a goal and Jamie Langenbrunner had the primary assist on both of Morrow's goals as the Pacific Division-leading Stars got back on track after dropping consecutive road games to Calgary and Vancouver by a combined 14-5.
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"Two stinkers and we finally came out and showed a little bit more life, did a better job taking away the shooting lanes and Kari was able to swallow up the other ones," Morrow said.
Lehtonen allowed all the goals in a 7-1 loss to the Canucks on Monday night in his worst showing of the season.
"When I feel like I didn't a good job, when I feel like I didn't help the team, I'm more focused on the next game," Lehtonen said. "I was able to help the guys and be part of the win and that always feels good."
Dustin Penner had a power-play goal for Edmonton, 4-14-3 in its past 21 games.
Nikolai Khabibulin made 18 saves for the Oilers in the second leg of a back-to-back. Edmonton won in Phoenix on Tuesday night, 4-3 on Penner's goal with 22 seconds left.
Edmonton held an 11-5 shots edge, but the Stars got the only goal of the first period at 10:38 when Burish's wrister from the right circle eluded Khabibulin.
Dallas moved to a 2-0 lead on its first power play of the night when Morrow notched his 20th of the season on a rebound at 2:32 of the second period.
Morrow converted Langenbrunner's centering pass at 8:23 of the second to make it 3-0.
Penner got the Oilers on the board at 17:44 of the second with a power-play goal, his 17th of the season.
Dallas won at Edmonton 4-2 last Thursday, and ill feelings carried over with four fights in Wednesday night's physical rematch.
Krys Barch of the Stars landed most of the punches in a second-period scrap with Zack Stortini, who spent most of the fight shielding his head with both arms. Barch ridiculed Stortini as he skated to the penalty box, mimicking Stortini's cover-up tactics. Barch received a 10-minute misconduct, and so did Dallas' James Neal as part of a fight with Theo Peckham later in the period.
Edmonton's Sam Gagner also drew a 10-minute misconduct in the third period for arguing with the officials, the kind of reaction that displeased coach Tom Renney.
"Tonight was one of those nights where you could show your mettle and be a real mature team and accept the battle and stay away from [complaining] and just play," Renney said. "That's what good teams do, take it for what it is and keep coming at you. We need to grow up and understand the value of that."
Khabibulin has lost his past 11 starts, but Renney said there's plenty of blame to go around.
"It's not a one-man deal at all, it's on everybody," Renney said. "It's on coaching, on players, on everyone who contributes on the ice. He needs run support, that's the bottom line."
Stars centers Jamie Benn and Tom Wandell missed the game with upper-body injuries sustained on Monday night in Vancouver.
So the All-Star break will allow those two and several other Stars to heal.
"We have a lot of guys that are playing with a lot of bumps and bruises right now," Stars coach Marc Crawford said. "The break could not come at a better time for us. We'll have four complete days where they'll get a chance to rest..."
Centers Aaron Gagnon and Travis Morin were called up from the AHL Texas Stars and both were in the lineup against the Oilers, with Morin making his NHL debut.
Edmonton is 0-7-1 in its past eight visits to Dallas. ... Dallas has 30 victories, something it wasn't able to do until March 16 last season. ... Stars D Jeff Woywitka sat out his third straight game with a shoulder injury. ... The Oilers were trapped in their end for several minutes midway through the second period. When Edmonton iced the puck three straight times, Renney used his timeout to settle his young team. ... Edmonton's penalty killers withstood a full 2 minutes of Dallas' 5-on-3 midway through the final period. ... Burish set a career high with his seventh goal.