Frankie Montas is back in the majors.

The veteran pitcher, who made his season debut after being reinstated from the injured list after missing the first 79 games of the season with a lat injury, threw five scoreless innings, striking out five and surrendering three hits and three walks in the Mets’ 7-4 loss.

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Manager Carlos Mendoza said he was happy with the performance.

“I thought he was good,” Mendoza said “I thought the ball was coming out well.”

Mendoza pointed to Montas’ signature sinker as his best pitch of the night.

Though many of the Braves hitters did not chase it, he was still able to generate a good number of groundballs.

Though he came through, it seemed like a risk to even start Montas against the division rival Braves. His numbers in the minors during his rehab assignment were less than inspiring.

In six minor league outings, Montas had a 12.05 ERA, allowing 25 earned runs over 18 ²/₃ innings and eight home runs.

But, especially in his last outing, Mendoza said Montas’ pitches were looking strong.

“That’s the kind of like the guy we saw in the playoffs,” Mendoza said, referring to facing Montas in the Mets’ wild-card series against Milwaukee last season.

Montas worked out of two jams with two runners on in the first and third innings. Each time, he was able to work out of dangers and keep the game scoreless.

Montas ended up with a no-decision as the bullpen imploded in the sixth inning.

When asked how it felt to be back with the Mets, he said he was just doing his job.

“I was just trying to go out there and … do my job, get people out,” Montas said.