The Pittsburgh Pirates scored three seventh-inning runs without the benefit of a hit to break a tie en route to a 6-4 victory over the host San Francisco Giants in the opener of a three-game series on Friday night.

After the Giants had used home runs by Steven Duggar and Alex Dickerson to erase a 3-0 deficit, the Pirates pieced together three walks, two infield grounders and a Giants error for the go-ahead rally in the seventh to snap a four-game losing streak.

Jacob Stallings drew a walk from Giants reliever Dominic Leone (2-1) to open the inning, after which San Francisco shortstop Thairo Estrada threw late to second base on Kevin Newman's grounder, putting two aboard.

Consecutive walks to Wilmer Difo and Adam Frazier forced in the inning's first run. The other two came home when Giants first baseman LaMonte Wade Jr. bobbled Ben Gamel's potential inning-ending grounder, allowing Difo and Frazier to score.

After dramatic last-inning comebacks in wins over the Los Angeles Dodgers the previous two nights, the Giants got within 6-4 in the ninth on a two-out RBI triple by Wade. But Pirates closer Richard Rodriguez struck out Mike Yastrzemski as the potential tying run for his 14th save.

Chris Stratton (3-0), who got the final two outs of the sixth, earned the win in a game in which neither starting pitcher got a decision.

Seeking a 22nd career win over the Pirates, Giants right-hander Johnny Cueto left for a pinch hitter in the fifth, trailing 3-1.

Pittsburgh got to the veteran for a single run in the second on an RBI triple by Gregory Polanco and went up 3-0 in the third on a two-run home run by Bryan Reynolds, his 18th of the season.

Cueto was charged with three runs on three hits in his five innings. He walked one and struck out seven.

The Giants rallied into a 3-3 tie against Pirates starter Chad Kuhl. Duggar led off the third with his seventh homer of the year, and Dickerson got San Francisco even with a two-run blast, his 10th, in the sixth.

Kuhl was pulled at that point, having allowed three runs and six hits in 5 1/3 innings. He walked one and struck out eight.

Reynolds had two hits for the Pirates, while Estrada and Buster Posey collected a pair apiece for the Giants. San Francisco out-hit the visitors 8-4.

--Field Level Media