SEATTLE (AP) — While Robbie Ray was again dominant against a potential playoff foe, there was a more important development for the Seattle Mariners on Sunday.

Perhaps All-Star Ty France is on the verge of breaking out of his extended slump and rediscovering the swing that made him one of best hitters in the American League during the first half of the season.

“We need Ty France’s bat back and it showed up today,” Seattle manager Scott Servais said. “I’m really excited about that.”

Ray tossed seven dominant innings, Dylan Moore and France homered and the Mariners beat the Cleveland Guardians 4-0 on Sunday.

Seattle took three of four from Cleveland in a potential postseason preview. All four games were tight and well-pitched, and the Mariners squeezed out just enough offense to earn a series victory.

The teams will run it back with a three-game set in Cleveland next weekend and perhaps again in October.

“We knew their games were going to be tight. We needed to play good defense and pitch well and we exceeded my expectations pitching-wise,” Servais said. “That’s about as good as you can pitch.”

The Guardians’ lead in the AL Central was trimmed to two games over Minnesota, which completed a sweep at home against San Francisco. Cleveland manager Terry Francona was complimentary of Ray’s performance and Seattle’s entire staff.

“Their entire staff is impressive. I mean, you’ve got your work cut out for you,” Francona said. “That doesn’t mean you can’t win, but you got your work cut out for you.”

Ray, last year’s AL Cy Young Award winner with Toronto, continued his August surge by winning his third straight start.

But Seattle’s offense has been meager of late in part due to France’s slump. He started the day hitting just .122 in August and was in an 0-for-21 slump when he singled in the fifth off Cleveland starter Aaron Civale.

France came back two innings later and hit the second pitch of the seventh inning out to left field for his 15th homer of the season.

“After the first hit, definitely felt like a weight was lifted off,” France said. “This whole series I felt like I was seeing the ball well, put a couple of good swings on balls and then today it was nice.”

Ray (11-8) scattered three hits, struck out seven and walked none. For the month, he allowed six earned runs and struck out 41 over 33 innings. He threw at least six innings in all five starts and permitted two earned runs or less in each one.

The left-hander escaped the one jam he faced. Andrés Giménez doubled and Austin Hedges followed with a bloop single to open the sixth. With runners at the corners and no outs, Ray got a fly ball from Myles Straw that wasn’t deep enough for Giménez to score, an infield popup from Steven Kwan and then struck out Amed Rosario for the third time to end the threat.

Cleveland was blanked for the eighth time this season, while Seattle posted its seventh shutout. During the Mariners’ six-game homestand, their starting pitchers went 2-0 with a 1.38 ERA. They had four walks and 39 strikeouts in 39 innings.

“Putting up zeros is the name of the game,” Ray said. “I feel like we’ve been doing a really good job of feeding off each other’s energy in our bullpen sessions and in the game. We’ve got a really good group.”

Moore broke the game open for Seattle with a three-run homer with two outs in the sixth off Civale. France hit a solo shot on the second pitch of the seventh.

Seattle also got a break just before Moore’s long ball. Moore fouled a 2-2 pitch wide of first base where Owen Miller made a leaping attempt into the protective netting to make the catch. But he bobbled the ball against the net and it was ruled out of play.

On the next pitch, Civale (2-6) left a curveball in the middle of the plate and Moore’s towering drive carried into the left field stands for his first homer since July 7.

Civale matched Ray into the sixth but has gone nine starts since his last victory back in late May. Civale allowed four hits and struck out five.

TRAINER’S ROOM

Mariners: SS J.P. Crawford was out of the lineup with an injury to his left pectoral muscle. Servais said after the game that Crawford had an MRI, but nothing major was discovered and he is day-to-day. Crawford had appeared in 115 of 127 games entering Sunday.

UP NEXT

Guardians: Cleveland returns home and, after a day off, will open a series against Baltimore. RHP Cal Quantrill (10-5, 3.59 ERA) starts the opener. Quantrill has won six straight decisions and threw seven shutout innings in his last start against San Diego.

Mariners: After an off day, rookie RHP George Kirby (5-3, 3.32) will make his 19th start Tuesday against Detroit. In August, Kirby is 3-0 with a 2.59 ERA and 29 strikeouts over four starts. He allowed one run over seven innings in his last outing.