(Photo credit: D. Ross Cameron-Imagn Images)

Andrew McCutchen broke a tie with a home run, the Pittsburgh bullpen threw seven innings of two-run ball and the Pirates ran their winning streak to three in a row with a 6-5 road triumph over the San Francisco Giants on Monday night.

Nick Gonzales also homered for the Pirates before Genesis Cabrera, Yohan Ramirez, Isaac Mattson, Dennis Santana and David Bednar picked up for an ineffective Mitch Keller, sending the Giants to their fourth straight home defeat.

After an early explosion produced a 4-3 Pirates lead after two innings, San Francisco tied the game in the fourth on a one-out double by Heliot Ramos and two-out RBI single by Willy Adames.

That run was charged to Cabrera. Ramirez (1-0) got out of the inning without further damage, then teamed with Mattson and Santana to shut out the Giants until the ninth.

Along the way, McCutchen produced the eventual difference-making run with his two-run shot to left field off Giants reliever Carson Seymour (0-1). The veteran's 10th homer of the season followed an inning-opening walk drawn by Tommy Pham.

The homer was the 329th of McCutchen's career, breaking a tie with Shawn Green and Mo Vaughn for 125th on the all-time list.

The Giants got within 6-5 in the ninth on a double by Adames and an RBI single by Jung Hoo Lee. But Bednar stranded the potential tying run at second by retiring Mike Yastrzemski on a pop fly to short and Patrick Bailey on a grounder to second, locking down his 17th save.

Gonzales' homer, his fifth, came on the eighth pitch of the game thrown by Carson Whisenhunt, who was making his major league debut.

The Pirates added three in the second on a two-out, two-run double by Isiah Kiner-Falefa and following RBI single by Pham.

Whisenhunt settled down after the second, eventually finishing five innings with four runs allowed on five hits. He walked two and struck out three.

The Giants ended Keller's night with a two-run second after a one-run first. Matt Chapman's triple, Brett Wisely's ground-rule double and Adames' first RBI on a single produced the scoring.

Keller was charged with three runs on five hits in two innings. He walked three and struck out three.

Gonzales and Pham had two hits apiece for the Pirates, who have won six of their last seven.

Adames totaled three hits and two RBIs for the Giants. Ramos had two hits and scored twice, while Bailey added a pair of singles.

--Field Level Media