SAN FRANCISCO -- For the first time as a starter this season, San Francisco Giants right-hander Ryan Vogelsong found himself trailing after having thrown just one pitch.

But he knew just what to do.

"After that," the veteran insisted, "my mind-set was: That's the last one they're going to get."

And that is was, as Vogelsong rebounded from a leadoff home run by Yunel Escobar to limit the Washington Nationals to one run in five innings, and four relievers pitched shutout ball the rest of the way to lead the Giants to a 3-1 victory Thursday night in the opener of a four-game series.

In the clubs' first meeting at AT&T Park since the 2014 National League Division Series, which San Francisco won 3-1, the Giants ended a five-game, regular-season losing streak to the Nationals.

"Nobody's really happy how things are going right now, but there's always tomorrow," said Nationals right-hander Stephen Strasburg, whose team lost its third in a row. "It's just one game. We've got Max (Scherzer) on the hill (Thursday)."

The Giants (61-53) won for just the second time in their past seven games and increased their lead over the Nationals (58-56) to three games. Both teams are chasing the Pittsburgh Pirates (66-46) and Chicago Cubs (65-48) for wild-card playoff spots.

Vogelsong (8-8) and right-handers Hunter Strickland, Sergio Romo and Santiago Casilla combined to hold the Nationals to five hits, one of them coming on the first pitch of the game when Escobar belted his eighth home run.

Most important, the quartet's final 136 pitches resulted in no runs after Vogelsong's first left the park.

It was Escobar's third leadoff home run of the season, but first on the first pitch of a game.

"I had an outside feeling he was going to be swinging," Vogelsong said after his first win as a starter since June 24. "I just didn't make good enough a pitch."

The Nationals got only two more hits off Vogelsong before he was pulled after five innings, having thrown 94 pitches. He walked four and struck out a season-best eight.

"The home run and the two hits," Vogelsong said. "You're going to take that on most nights."

Casilla recorded his 28th save with a scoreless ninth inning, striking out pinch-hitter Danny Espinosa as the potential tying run after allowing a two-out double to center fielder Michael Taylor.

"We're doing good things, but we're just not scoring runs," said Nationals shortstop Ian Desmond. "That just comes in time and believing in yourself. If you can't believe in this team, I don't think there's a team out there you can believe in."

After Escobar homered in the top of the first inning, it took the Giants just seven pitches to tie the score and 14 to take the lead.

Center fielder Gregor Blanco led off the Giants' first with a triple and scored on third baseman Matt Duffy's RBI single to right field. After first baseman Brandon Belt drew a walk, catcher Buster Posey grounded an RBI single to left field, scoring Duffy.

"Amazing. That was huge for us," said Blanco, who also scored the Giants' third run in the seventh inning after his ninth stolen base and an RBI single by Belt. "I was just trying to pump guys up. That's my job -- being the energy guy."

Second baseman Kelby Tomlinson also tripled for the Giants, and Posey had two of the team's eight hits. San Francisco handed the Nationals their 10th loss in their last 14 games.

Strasburg (6-6) took the loss, his first in a regular-season game against the Giants. He allowed two runs on seven hits in six innings. He walked two and struck out eight.

Right fielder Bryce Harper had two hits, a walk, a stolen base and an outfield assist for the Nationals, who are now just 1-3 to start a 10-game trip.

The assist came on a strong throw to home plate to nail a sliding Posey in the third inning after a single by Giants right fielder Hunter Pence.

NOTES: 3B Matt Duffy's RBI single in the first inning snapped the Giants' 0-for-23 streak with runners in scoring position. ... The Giants placed LF Nori Aoki on the seven-day concussion disabled list before the game. Aoki was hit in the head with a pitch by RHP Jake Arrieta on Sunday and experienced dizziness when he returned to game action Wednesday. OF Ryan Lollis was recalled from Triple-A Sacramento to take Aoki's spot on the Giants' roster. ... Giants RHP Mike Leake (strained left hamstring) threw a two-inning simulated game on Thursday and experienced no setbacks. He is tentatively scheduled to be activated from the DL on Tuesday and start at St. Louis. ... Nationals OF Reed Johnson (torn tendon in left foot) began an injury-rehab stint at Class A Potomac on Thursday. Johnson hit .222 in 12 games for Washington this season before undergoing surgery. ... Former basketball great Bill Walton participated in on-field Grateful Dead Tribute Night festivities before the game, including the singing of the national anthem.