Sandoval's out three-run double was the big hit in a 10-run fourth inning. He also hit a pair of sacrifice flies.

Six others had one RBI and a total of five players had two hits for the Giants, who won twice in the three-game series.

The winning pitcher was reliever Osiris Matos (1-2).

Pittsburgh's Jason Michaels had two hits and two RBI. Steve Pearce and Robinzon Diaz both had two hits and one RBI.

One run scored on Eugenio Velez's third-inning error, while four players had two hits for the Pirates, who have dropped three of four and 17 of 22 overall.

The losing pitcher was starter Jeff Karstens (2-5).

All-star center fielder Nate McLouth suffered a facial injury on Sandoval's big hit.

Pittsburgh's loss guaranteed its 16th straight losing season.