SAN FRANCISCO -- When you have won three championships in five years, you don't waste your energy dumping a bucket of ice over the head of the star of the game.

So San Francisco Giants center fielder Gregor Blanco took matters into his own hands Friday night when it came to cooling himself down following his club's 8-5 victory over the Washington Nationals.

"My legs are tight," Blanco admitted following an all-around brilliant effort that included two doubles, a bunt single, a stolen base and a great catch in the outfield. "I just took a cold tub. That always helps."

Blanco and third baseman Matt Duffy combined for six hits and five RBIs out of the top two spots in the lineup, and right fielder Hunter Pence added a home run, as the Giants recorded a second consecutive victory over the Nationals.

Giants manager Bruce Bochy was so concerned about Blanco's nonstop performance, he said he'd consider giving him the night off Saturday.

"He had a terrific game," Bochy said of Blanco. "Great slide (at home plate), perfect bunt, catch in the outfield ... He did it all tonight.

"He played with a lot of fire. He can do a lot of things for you. He's an exciting player."

Duffy was equally impressed.

"He put on a clinic," he said of Blanco. "Exactly what you want out of a leadoff batter. I don't want to use the word perfect, but he was close to perfect tonight."

As was the Giants bullpen. Five relievers rescued starter Matt Cain with 4 1/3 shutout innings as San Francisco won for the 11th time in its last 13 home games and improved to 3-1 on its current six-game homestand.

"They really bailed us out," Bochy assured. "That's what you need."

It became needed after Nationals star Bryce Harper belted a three-run homer, his 30th of the season, in a four-run fifth inning that ended Cain's night and rallied the Nationals within 6-5.

But Washington managed only one more hit and couldn't score again against Giants relievers Jeremy Affeldt, George Kontos, Josh Osich, Sergio Romo and Javier Lopez.

Affeldt (2-2), who took over for Cain with two men on and shut down the fifth inning, was credited with the win. Lopez, who got Harper to fly out to end the game, recorded his first save.

"That's unbelievable," Cain said of the bullpen work. "Jeremy comes in right there. Huge situation. It shut their momentum down and gave us a chance to add on."

Duffy drove in three runs with three hits, including his 10th home run, for the Giants, who led 6-1 after three innings and chased Nationals starter Max Scherzer at that point.

Two of Blanco's hits were doubles, the first of which came in a four-run second inning during which the Giants tied a West Coast franchise record with four two-base hits.

Six of San Francisco's seven hits off Scherzer went for extra bases.

"I understand what caused tonight," the Nationals ace admitted. "It's very frustrating because we need wins. But I'm confident I can fix this within five days and go out there and give us a chance to win."

After the Nationals got within 6-5, the Giants scored the final two runs of the game on an infield out by first baseman Brandon Belt in the sixth inning and a sacrifice fly by Duffy in the eighth.

Belt and Pence added two hits apiece for the Giants, who out-hit the Nationals 13-7.

Harper drove in a total of four runs, and second baseman Danny Espinosa had a solo homer for the Nationals, who have lost four row and 18 of 28 since the All-Star break.

"I want to hit 40 or 50. Keep going, keep battling," Harper said of reaching the 30-homer mark. "If I'm doing that, we're going to win ballgames, and that's all that matters."

Left fielder Clint Robinson added two hits for Washington.

Scherzer (11-9), who last faced the Giants for Detroit in Game 4 of the 2012 World Series, a game won by San Francisco 4-3 in 10 innings to complete a four-game sweep, was roughed up for six runs on seven hits in three innings. He struck out three and did not walk a batter.

The three-inning outing was his shortest of the season, and the six runs allowed were a season high.

Cain was charged with five runs and six hits in 4 2/3 innings. He walked one and struck out three.

NOTES: The four-double inning was the Giants' sixth since moving west in 1962. ... The three-hit game was Giants 3B Matt Duffy's 12th of the season. ... RF Bryce Harper became the sixth player in Nationals history to hit 30 home runs in a season. 1B Adam LaRoche was the last to do it in 2012. ... Nationals RHP Max Scherzer has allowed 11 home runs in his last eight starts after having surrendered just seven in his first 16 outings. ... Nationals manager Matt Williams benched three of Thursday's starters -- OF Jayson Werth, INF Anthony Rendon and C Wilson Ramos. Werth and Rendon served as pinch-hitters late in the game. ... Injured Nationals 2B Dan Uggla (back spasms) received his World Series championship ring from the Giants before the game. Uggla went 0-for-11 with a walk, a run scored and six strikeouts in four games for the Giants last July before getting waived.