Buster Posey cleared the bases with his fifth career grand slam in the top of the 10th inning Friday night, sending the San Francisco Giants to a 10-7 victory over the host Milwaukee Brewers in the opener of a three-game series.

After both teams had scored one run in the ninth, Joe Panik singled off the Brewers' fifth pitcher, Matt Albers (4-3), to lead off the 10th. After Mike Yastrzemski worked a walk and Brandon Belt singled to load the bases, Posey connected for just his fourth home run of the season, his first since June 1.

The grand slam was Posey's first since June of 2015 and the second of his career at Milwaukee. He had his first off the Brewers' Chris Capuano in 2010.

Posey had been 0-for-3 with three strikeouts with the bases loaded this season.

Keston Hiura's solo homer off Mark Melancon in the last of the 10th completed the scoring and gave the rookie a three-hit game.

Brandon Crawford hit a tie-breaking home run off All-Star Josh Hader with two outs in the top of ninth, putting his team up 6-5. That came one inning after Tyler Austin greeted Hader with a first-pitch, pinch-hit homer to draw the Giants even in the eighth.

But Giants All-Star closer Will Smith couldn't retain the lead in the last of the ninth, allowing a leadoff triple to Christian Yelich and a one-out RBI groundout to Mike Moustakas that tied it at 6-6.

Both starting pitchers worked five innings, and neither got a decision.

The Brewers' Chase Anderson limited the Giants to two runs on three hits in his five innings and left the game with the score tied 2-2. The two runs off Anderson came on a home run by Austin Slater in the fifth inning after Kevin Pillar had doubled.

Evan Longoria belted a two-run shot of his own in the sixth off Brewers reliever Corbin Burnes to put the Giants on top 4-2.

But San Francisco's Shaun Anderson allowed a walk to Yasmani Grandal and a double to Moustakas before getting pulled in the last of the sixth. Ryan Braun tied the game with a two-run double, before Eric Thames gave the Brewers a 5-4 lead with an RBI single.

The Giants' Anderson was charged with four runs on six hits in his five innings.

Despite allowing a run in his only inning and recording his first blown save of the season, Smith (2-0) was awarded the win.

--Field Level Media