Updated

Madison Bumgarner took a no-hitter into the sixth inning and struck out 10 batters in San Francisco's 6-0 win over the Atlanta Braves in the opener of a three-game series.

Bumgarner (6-4), who gave up two hits and one walk over seven frames, has 21 strikeouts in two starts against Atlanta this season.

Buster Posey doubled three hits, drove in a run and scored twice for the Giants. Gregor Blanco led off the game with a homer, as the Giants posted their second straight shutout after blanking the Pirates 10-0 on Thursday.

Kris Medlen (3-7) gave up nine hits and four runs over six innings and fell to 0-4 lifetime against the Giants.

The Braves, losers of four in a row, had just three hits.

Blanco homered to right on the game's fourth pitch and he made it 2-0 the following inning when his soft line single to right plated Joaquin Arias.

"It's huge and we know that," Blanco said of the early runs. "That shows that we're ready from the leadoff spot. We got momentum and we just kept going."

Posey and Hunter Pence hit consecutive doubles to start the third. Pence's hit came when center field B.J. Upton failed to make a shoestring catch.

Brandon Crawford's double to left on an 0-2 pitch scored Posey in the fifth for a 4-0 lead.

Making his fourth consecutive start on the road, Bumgarner was flawless until walking Upton with two outs in the fifth and his first hit allowed came to Chris Johnson leading off the sixth. The ball dropped between three fielders in right-center.

"He was real tough. He's always tough," Johnson said of Bumgarner. "He throws a lot of pitches for strikes, a lot of different pitches for strikes. He keeps you guessing. He pounds the zone. He was on."

The Giants tacked on two runs in the seventh, one on a double to right-center from Posey and another on a bases-loaded balk from Alex Wood.

Game Notes

The Braves scratched right-hander Brandon Beachy from Tuesday's start against the New York Mets. Beachy hasn't pitched this season as he recovers from elbow surgery. Braves general manager Frank Wren said Beachy's elbow is still tender ... Since 1994, San Francisco has won only two series in Atlanta (went 3-1 in 2008 and 2-1 in 2012), going a combined 24-51-1. The Giants are trying to win back-to-back series in Atlanta for the first time since April 11-12 and June 8-10, 1990 ... Atlanta right fielder Jason Heyward went 0-for-4 and had his 10-game hitting streak snapped.