PITTSBURGH -- Exactly one year ago, Chris Archer took the mound at PNC Park for the first time in a Pirates uniform. He warmed up to Wiz Khalifa’s “Black and Yellow.” The crowd roared before every two-strike pitch. The outing itself was unremarkable, but Archer -- the Pirates’ big Trade Deadline prize last summer -- walked off the field to a standing ovation.

Considering his struggles over the past year, there was far less anticipation in the sold-out crowd as Archer warmed up Saturday night to Outkast’s “So Fresh, So Clean.” If anything, the excitement was for Marcus Stroman, making his post-trade debut for the Mets like Archer did for the Pirates a year ago. Archer satisfied the crowd with the kind of start Pittsburgh expected from him, working six strong innings, only for the bullpen to blow the lead in a 7-5 loss.

The Pirates have lost 17 of their 21 games since the All-Star break. They will need to beat the Mets on Sunday afternoon to avoid losing their seventh straight series.

• Box score

Has it really been a year since the Pirates first sent Archer to the mound, confident that their bold Trade Deadline moves would set them up to contend not only in 2018 but in ‘19 and beyond?

“The time’s gone by pretty fast, it really has,” Archer said. “Hasn’t been the greatest from a results standpoint, but I feel like I have grown as a pitcher. It doesn’t show up in the box score, necessarily, but I feel good with where I’m at.

“I like this team. I like this organization. Since the All-Star break, it hasn’t been pretty, but we’ve got to remember this team’s super young.”

The night was not devoid of silver linings. Adam Frazier, Bryan Reynolds and Starling Marte combined for nine of the Pirates’ 10 hits. Reynolds finished 4-for-4, raising his average to .333 and his OPS to .920. Marte stole two bases on the night and launched his 20th home run of the season, scoring two runs to cut the Pirates’ deficit in half in the ninth.

“He’s unbelievable. Opportunity to be the best player every night on the field,” Pirates bench coach/acting manager Tom Prince said of Marte. “It’s very fun to watch him. … He’s one of the elite players in the game, in my opinion.”

And there was a reason to feel good about Archer, who allowed one run on five hits and two walks while striking out six and pushing through six innings despite a 33-pitch first. He threw 65 of his 95 pitches for strikes and induced 14 swinging strikes while mostly throwing a mix of four-seam fastballs and sliders.

But the Bucs’ thinned-out bullpen, working without setup men Keone Kela (suspended) and Richard Rodriguez (paternity list), sent the Pirates’ faithful home with a bad taste in their mouths.

Right-hander Michael Feliz gave up a pinch-hit homer to Jeff McNeil in the seventh, then setup man Kyle Crick allowed a leadoff double to Robinson Cano in the eighth before Wilson Ramos ripped the go-ahead homer to right field. Ramos struck again in the ninth against Chris Stratton, crushing a three-run double over right fielder Pablo Reyes and off the Clemente Wall.

“If he gets his arms extended, anything middle-away, he does damage,” said Archer, who was Ramos’ teammate in Tampa Bay. “The homer was kind of in his wheelhouse, like middle-away, and he drives the ball the other way just as good as anybody in the game.”

The night began in ominous fashion for Archer, fresh off an outing in which he allowed six runs in the first inning at Citi Field. Four of the Mets’ first five hitters on Saturday night reached safely. One run, one out and 23 pitches into the game, pitching coach Ray Searage made his first mound visit.

After stepping off the mound and reminding himself to trust his stuff, Archer struck out J.D. Davis and escaped the inning with a comebacker from Todd Frazier.

“What I possess is good enough,” Archer said. “Whenever you’re not forcing things and you’re allowing things to happen, you’re much better off. That’s what happened after I stepped off and collected my thoughts.”

The Pirates gained a lead by scoring two runs against Stroman, Archer’s close friend and the Mets’ surprising Trade Deadline acquisition. Frazier, Reynolds, Marte and Josh Bell began the first inning with consecutive singles, then Jose Osuna forced in a run with a bases-loaded walk. After chasing Stroman in the fifth, Osuna walked to load the bases and another run scored when Kevin Newman was hit by a pitch.

Archer needed 19 pitches to get through a scoreless second inning, then he settled down. He threw 15 pitches in the third then faced the minimum in the fourth (eight pitches), fifth (10) and sixth (nine). It was Archer’s sixth quality start in 20 outings and only the fourth time this season he hasn’t allowed a home run.

“When he’s on top of his game, that’s what he does,” Prince said. “After that first inning, I think he did a really good job.”