SAN FRANCISCO -- On the day the Giants honored Hall of Fame pitcher Juan Marichal, left-hander Madison Bumgarner gave San Francisco a performance worthy of the high-kicking Dominican.
Bumgarner homered and doubled, and struck out 14 while pitching a three-hitter as the Giants beat Washington 5-0 Sunday, handing the Nationals their sixth straight loss.
Bumgarner joined Marichal as the only San Francisco pitchers to throw a shutout, strike out at least 10 and hit a home run in the same game.
"It's a pretty big day, he means a lot to the organization," Bumgarner said. "It's really neat for the Giants to bring guys like that back. It's really special."
Hunter Pence also homered as the playoff-contending Giants finished off a four-game sweep, outscoring the Nationals 28-12.
Washington matched its longest skid of the season. A popular pick before opening day to win the World Series, the Nationals fell below .500 at 58-59.
"We've played terrible the last 15 or 16 games and we faced one of the best today," Nationals first baseman Ryan Zimmerman said. "He might be the best in the bigs right now."
Bumgarner (14-6) held the Nats hitless into the fifth inning. The World Series MVP matched his career high for strikeouts while pitching his first shutout of the year and fourth overall in the regular season.
"He did it all. That's an impressive outing with how hot it was," Giants manager Bruce Bochy said. "That was an old-school type game; starter goes nine was fitting. Marichal did it so many times. Bumgarner, that's back-to-back for him."
Bumgarner has an ERA of 0.71 in the three games since allowing six runs in seven innings to the Texas Rangers. He has 35 strikeouts in 25 1/3 innings during that span.
"You can always do better," Bumgarner said. "But this would be tough to beat . the way things are going for me."
Bumgarner hit an RBI double early and later connected for his fourth home run of the season and 10th of his career.
The big lefty permitted just three singles, and no runner made it past second base.
Joe Ross (3-5) struck out the first four Giants and threw three perfect innings before running into trouble in the fourth.
Ross lasted a season-low four-plus innings, allowing four runs on six hits. He walked one and struck out six.
Brandon Belt hit an RBI double in the fourth and scored on Pence's homer.
Nationals: OF Bryce Harper was back in the lineup less than 24 hours after fouling a ball off the top of his foot. Harper reported it was still painful after Saturday night's game but that he was encouraged that X-rays were negative. "I got it pretty good," Harper said. "It felt terrible at the time."
Giants: OF Angel Pagan (right patella tendinitis) and 2B Joe Panik (lower back inflammation) will go to Arizona to continue their rehabs when the Giants leave on their road trip. ... RHP Mike Leake is set to come off the disabled list in time to start Tuesday's game against the Cardinals.
Nationals: Following an off-day, the Nationals hope to salvage their road trip when they begin a three-game series at Colorado.