SEATTLE -- It took a few batters for right-hander Mike Leake to get settled in when he made his Seattle Mariners debut. After that, he looked like a pitcher who could keep the Mariners in a playoff chase for a while.

Leake pitched seven innings and allowed two runs as the Mariners defeated the Oakland Athletics 3-2 on Friday night, snapping a five-game losing streak.

"It's nice to finally be here," said Leake, who was acquired from the St. Louis Cardinals on Wednesday.

The Mariners (67-68) probably couldn't agree more after cutting the gap for the last playoff spot to 3 1/2 games. The Athletics (58-76) lost their fourth straight.

After spotting the Athletics two early runs during early struggles, Leake (8-12 overall, 1-0 with Seattle) didn't let Oakland have anything the rest of the way. Leake allowed eight hits with a walk and seven strikeouts.

A three-run burst in the third highlighted by a Mike Zunino solo shot and Kyle Seager's go-ahead sacrifice fly was all the Mariners needed.

Leake and Seattle's bullpen made it hold up as Mark Rzepcynski , Nick Vincent and Edwin Diaz pitch two shutout frames to keep the Athletics at bay, with Diaz notching his 31st save.

He outdueled Oakland lefty Sean Manaea (9-9), who pitched 6 2/3 innings, giving up three earned runs. But to Athletics manager Bob Melvin, Manaea's outing was good to see.

"He pitched today like we've seen him pitch earlier in the season," Melvin said. " ... As far as his stuff goes, it was the best we've seen in a while."

As for Leake, Zunino could tell his new pitcher was beginning to find his way

"He settled in and started using all of his pitches, coming in and out of the zone," Zunino said. "That's really when he settled in."

The cherry on the sundae was Leake pitching his way out of a jam in the seventh after Matt Chapman doubled to right-center field and took third on a wild pitch with one out. But Leake, who generally pitches to contact, struck out Boog Powell and Marcus Semien to end the threat.

Early on, Leake looked extremely shaky.

The Athletics immediately got to the right-hander with three consecutive hits, singles to center by Marcus Semien and Matt Joyce followed by Jed Lowrie's RBI double down the right-field line. Matt Olson added an RBI groundout for a 2-0 lead in the top of the first.

Leake got out of the trouble by stabbing Ryon Healy's shot up the middle and firing to first to retire the side. Little did the Athletics know, their offense would be quiet after that.

"We made him find throw the ball over the middle of the plate in the first three innings," Melvin said of Leake. "Then he got better after that."

The Mariners posted their own rally in the third, adding three runs to take a 3-2 lead.

Zunino cut into the lead in the third with his 20th homer, a solo shot off Manaea that snuck inside the right-field foul pole. Mitch Haniger evened the score at 2-2 later in the inning with an RBI single to center.

After Manaea hit Robinson Cano and walked Nelson Cruz to load the bases, he gave up a go-ahead sacrifice fly to Seager.

That turned out to be just enough.

NOTES: Mariners RHP Felix Hernandez threw a bullpen session on Friday, his first action off a mound since going on the disabled list on Aug. 5 with bursitis in his pitching shoulder. LHP James Paxton (pectoral strain) is scheduled for a bullpen session on Saturday. ... The Mariners promoted RHPs Dan Altavilla, Ryan Garton and Andrew Moore and activated OF Jarrod Dyson and RHP Shae Simmons from the disabled list. RHP Sam Gaviglio was claimed on waivers by Kansas City and RHP Christian Bergman was sent down to Triple-A Tacoma. ... Oakland promoted SS Franklin Barreto and LHP Sam Moll from Triple-A Nashville; they also activated C Josh Phegley (left oblique) and CF Jake Smolinski (shoulder surgery) from the disabled list. ... Moll made his major-league debut in the eighth inning, and got pinch-hitter Yonder Alonso to fly out to left.