WASHINGTON -- Anthony Rendon continued his hot streak at the plate, hammering a three-run homer in the first inning to help guide the Nationals to a 5-1 victory against the Mariners on Wednesday night at Nationals Park. Washington jumped on Seattle for four runs in the first and added another in the second against rookie right-hander Sam Gaviglio.
The early runs provided a cushion for Nats righty Tanner Roark, who rebounded from a rough stretch with seven innings of one-run ball and eight strikeouts.
"He got through the early innings without a high pitch count," Nationals manager Dusty Baker said of Roark, who got through the seven frames with 102 pitches. "That's what's been plaguing him the last three or four starts. He was sharp today and had a real good slider and he had real good command of his fastball."

Gaviglio, who was making just his second career start, settled in against the Majors' top offense after giving up five runs in the first two innings, not allowing a run over his final four frames. All four first-inning runs were unearned after Jean Segura committed a throwing error on Trea Turner's leadoff grounder. Gaviglio gave up five runs on six hits in six innings, but the slumping Mariners offense could not push across any more runs after an RBI single by Robinson Cano in the first. That made it five straight games -- all losses -- in which Seattle has scored just one run.

"You get in a five-run deficit in the first, second inning, in the grand scheme of things that's something you can fight out of and you can bounce back from," said Mariners third baseman Kyle Seager, who scored the lone Seattle run. "We haven't just done that. We need to do a better job with that."
• Slumping Mariners not making excuses
Koda Glover finished off a 1-2-3 ninth inning in a non-save situation, but after the game Baker confirmed Glover will serve as his primary closer.

"We wanted to break him in slowly because this guy's, shoot, he's only a year and a half out of college," Baker said. "So he had said that's the job he wanted, and so it's his now. He's very calm. He throws strikes, quality strikes, and he has a pretty good idea of what he's doing for a young pitcher."
• Glover officially named closer
The Nationals continued to dominate the Mariners in these Interleague matchups, particularly in Washington. The Nats are now 8-0 against Seattle in D.C. since they returned here in 2005, and they will try to complete a three-game sweep on Thursday afternoon.

MOMENTS THAT MATTERED
Rendon stays scorching: Rendon gave the Nationals the early cushion they needed with his third home run in his last two games. Per Statcast™, his first-inning three-run shot off Gaviglio left the bat at 100 mph with a launch angle of 34 degrees, traveling a projected 391 feet to the Mariners' bullpen in left-center field. After a quiet start to the season, the Nats' third baseman has hit eight home runs and driven in 26 runs since April 30.

Roark ends Seattle's potential rally: Trailing from the first inning on, the Mariners found their best chance to get back in the game in the sixth inning, with Mike Zunino at the plate and runners at the corners with two out. But Roark, who delivered arguably his best outing of the season, ended the Seattle threat by getting the catcher to swing through a full-count two-seam fastball. Roark finished with eight strikeouts on the night, tying a season high.
"I felt like the two-seamer was moving, so that's a positive itself," he said. "That's my biggest thing, my two-seamer working. I was hitting my spots." More >
QUOTABLE
"You keep doing that, playing the game the right way over and over and over again, things turn. That's the only way they turn. Just thinking somebody's going to walk up there and hit a couple homers one night or somebody's going to throw a shutout, it doesn't usually work that way. It's a collective effort, and that's what we got to get to. -- Mariners manager Scott Servais, on his team trying to snap a five-game skid
WHAT'S NEXT
Mariners: Seattle ends its series in D.C. with a matinee due to expected inclement weather on Thursday. So the Mariners will send lefty Ariel Miranda to counter the Nats southpaw Giovany Gonzalez at 9:05 a.m. PT.
Nationals: Left-hander Gio Gonzalez will take the mound as the Nationals go for a three-game sweep of the Mariners on Thursday afternoon at 12:05 p.m. ET at Nationals Park.
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