WASHINGTON -- An unusually short start from Kevin Gausman in his first loss of the season, combined with a lack of offense, led to the Giants’ 2-0 defeat to the Nationals in Game 1 of Saturday’s split doubleheader.

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Prior to Saturday’s games at Nationals Park, Gausman had allowed five home runs this season, three of which came in the first inning. The trend continued when Kyle Schwarber smacked a 426-foot leadoff home run on Gausman's second pitch of the game. It was the right-hander's first earned run allowed in 24 innings pitched, dating back to May 14.

“I was trying to throw a fastball up, and then ... I'm pretty sure it was middle middle,” said Gausman. “[Schwarber] doesn't miss those pitches. It's not how I wanted to start the game, obviously. They battled me, especially that first inning, but really, throughout the whole game. I felt like they did a good job of laying off some tough pitches and making me work.”

Gausman settled in after that opening frame, retiring six consecutive batters and keeping it a one-run game until the fourth inning. After a seven-pitch walk to Juan Soto, his second free pass of the day, Gausman gave up an RBI double to Josh Harrison.

Gausman tossed just 64 pitches over his four innings of work, his shortest outing of the season and his shortest in a Giants uniform. That part had nothing to do with the right-hander’s ability, according to manager Gabe Kapler, who needed to jumpstart his offense.

San Francisco put together only five hits and left four on base in the opener. It marked just the third time this season the Giants had been shut out.

“Today we are a little bit sluggish,” said Kapler. “I also think we came out without the most enthusiasm that we've had all year. It's not an effort thing; I just think we may have been a little bit sluggish in general. Perhaps a bit of fatigue? We're going to energize the group now to the best of our ability to get ready for Game 2.”