PITTSBURGH — Two innings into Sunday’s series finale against the Pirates, things looked bleak for the Arizona Diamondbacks. Rookie sensation Paul Skenes was on the PNC Park mound and had a four-run lead to work with, a gap which held through five innings.

But the D-backs managed to chase Skenes from the game during a two-run sixth inning, then Joc Pederson’s three-run homer in the seventh off Colin Holderman gave Arizona its first lead en route to a 6-5 win over the Pirates.

“I mean, you’re facing probably the hottest pitcher in baseball right now and they’re able to get a four-run lead to him and it’s like, ‘Oh man, game’s over,’” Pederson said. “But we got him out in the sixth inning and were able to capitalize on that.”

The D-backs knew they were in for a battle against Skenes, and no one knew that better than manager Torey Lovullo — who, as skipper of the NL All-Star team, gave the right-hander the start in the Midsummer Classic.

“I think that the world felt like their starting pitcher was going to have a really good day and walk all over us,” Lovullo said. “But there were 26 men in that clubhouse that made a stand and said that we would have a different outcome than the world thought.”

It wasn’t that the D-backs hit Skenes hard — at least, not until the sixth — but the game plan all along was not based on that. Instead, the goal was to wear him down with each at-bat, hopefully raising his pitch count to get him out of the game sooner than later.

It didn’t work in the first, as Skenes retired the side on 10 pitches, but they made him throw 22 in the second inning, and after a 12-pitch third, they worked him for 23 pitches in the fourth and 17 in the fifth.

“He’s got great stuff,” Lovullo said. “We just thought that if we can grind him down a little bit, 15-plus pitches per inning, just find a way to get him out of the game. And it happened in the sixth inning, and I think he got a little fatigued, maybe missed a couple spots and left with a little bit of traffic on the bases.”

Still, the two-run rally in the sixth wasn’t enough with the D-backs still down 4-2 heading into what proved to be a decisive seventh inning.

The Pirates brought in Holderman to start the inning and after a pair of walks gave the D-backs runners at first and second with two outs, Pirates manager Derek Shelton faced a decision.

With the left-handed Pederson coming up, Shelton could have brought in Jalen Beeks, who was throwing in the bullpen at the time. Had he done that, Lovullo said he would have gone to the right-handed-hitting Lourdes Gurriel Jr.

Instead, Shelton stuck with Holderman and Pederson hit a 1-2 fastball on the outer edge of the plate over the wall in left for the homer.

“They had a potential matchup and they [instead] chose to challenge Joc, and I think he took that personally,” Lovullo said.

Pederson downplayed how he felt about the matchup.

“I mean, it is what it is,” he said. “There’s a lot in this game you can’t control. Just take what the game gives you, and it was another opportunity and I was just going to do my best to help the team win.”

Ketel Marte added a solo homer in the ninth to give the D-backs some insurance, which they would need when the Pirates staged a rally in the bottom of the frame.

With the win, the D-backs have now won six straight series, and they have won or split their last 10 series and 16 of their last 18 since May 30. A lot of that has to do with getting back a number of key contributors that were on the injured list.

“I think we’ve got all our pieces and there’s consistency with the lineup,” Lovullo said. “There’s continuity, and this group knows what each at-bat is asking for. We have a bunch of winning players on this team. They know that you give us an extra out, you give us anything, we’re going to take advantage of it, and we’ve been doing a great job of that.”