PITTSBURGH — Two dominant starting pitching performances and quality offensive showings later, the Mets’ ship is sailing again.

The 1-2 combo of Chris Bassitt and Jacob deGrom was too much for this boatload of Pirates, who were equally flustered in trying to contain the likes of Eduardo Escobar, Tyler Naquin and Francisco Lindor over 18 innings on Wednesday.

It translated into a needed Mets doubleheader sweep.

The Mets won the opener 5-1 to snap a three-game losing streak. In the nightcap, they rolled 10-0 at PNC Park for momentum heading into their weekend series in Miami.

The doubleheader sweep gave the Mets a half-game lead on the Braves for first place in this NL East dogfight. A night earlier, the Braves had joined the Mets in first place for the first time this season.

“It’s going to be a tight race and it should be a tight race,” Lindor said. “[The Braves] have a good team and Philly as well. Three teams are competing for the playoffs in this division and have really good ballclubs. Let’s see if we can lose less than they do.”

On a day the Mets lost Max Scherzer for at least two starts — he was placed on the injured list with left oblique irritation — the team issued a reminder about the depth of this rotation.

In the nightcap, deGrom fired seven shutout innings and struck out eight with three hits allowed and one walk. It was a second straight appearance in which deGrom completed seven innings. He lowered his ERA to 1.66.

“I threw a lot of changeups,” deGrom said. “I had a great feel for it from my previous starts and have been working on it in between. I felt like my changeup was real good. I think I ended up throwing like 14 of them, that was a huge plus for me and definitely going to be a huge plus moving forward.”

Escobar homered in Game 1, but saved his best work for the nightcap, in which he finished 4-for-5 with an RBI. Naquin delivered a three-run blast in the first game and went 2-for-4 in the nightcap. Lindor stroked two doubles and drove in three runs in the nightcap.

“Our guys were frustrated coming in a little bit. … They knew they were capable of better,” manager Buck Showalter said. “A lot of good at-bats, a lot of walks. I thought we got patient there too from trying to do too much.”

Bassitt steered the rotation back on its expected course with quality and length in Game 1. If not his best performance of the season, it might have been Bassitt’s biggest given the team’s recent play. Bassitt allowed one earned run on five hits with 10 strikeouts and one walk over seven innings.

Scherzer, Carlos Carrasco and Taijuan Walker had previously failed to pitch beyond the fifth inning.

“I’m sure the world was going crazy, but we’re fine,” Bassitt said.

Early homers from Naquin and Escobar accounted for most of the Mets’ scoring, leaving Bassitt with a comfortable lead to protect against these last- place Pirates.

Naquin — starting in right field a day after Starling Marte was drilled by a pitch on the right hand and departed the game — blasted a three-run homer in the fourth inning against Bryse Wilson that gave the Mets a 4-0 lead. The homer was Naquin’s fourth since arriving from the Reds on July 30.

After Naquin homered, Escobar followed with another, extending the Mets’ lead to 5-0. The back-to-back homers were a fifth-time occurrence for the Mets this season.

Escobar’s homer was his third in five games, continuing a surge from the switch hitter since he returned from an oblique strain that placed him on the injured list.

“I haven’t done anything much different from what I have done from the beginning of the year,” Escobar said. “I think the biggest difference of what I have done is swinging at pitches inside the strike zone, so I think when you swing at good pitches you have good results.”

Though the Pirates announced 8,717 as attendance there might not have been more than 2,000 fans in the ballpark for Game 1 — a makeup from a Monday postponement.

“In this environment you have got to challenge yourself to pitch with that intensity, the first game of a doubleheader,” Showalter said. “That is typical Chris, we have come to expect that from him.”