NEW YORK -- When J.D. Martinez joined the Mets last weekend, team officials had a choice. They could designate well-liked infielder Zack Short for assignment, perhaps ending Short’s time in the organization, or they could send DJ Stewart to the Minors. Short was out of Minor League options, which always plays a role in these sorts of decisions. But Stewart fit better on the roster. He had proven his worth throughout the early season. The Mets wanted to keep him around.

The wisdom of that decision became apparent on Tuesday, when Stewart hit a tiebreaking three-run homer in the sixth inning of New York’s 4-2 win over the Cubs. Of Stewart’s four home runs, three have given the Mets a lead.

“There was a cloud on top of him,” manager Carlos Mendoza said. “I’m just glad that he’s having a big impact on our team right now.”

Much as he did earlier this year in Atlanta, Stewart provided the late charge the Mets needed Tuesday at Citi Field. Listless for much of the early evening, New York’s offense came alive when Cubs shortstop Dansby Swanson committed a throwing error with one out in the sixth. Tyrone Taylor followed with a two-out single, which brought Stewart to the plate.

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Facing former Cubs closer Adbert Alzolay, Stewart clubbed a belt-high cutter into the second deck in right field. As Stewart dropped his bat, the stadium lights dimmed, flashing intermittently while he rounded the bases.

“There isn’t really a feeling when you hit the ball flush like that,” Stewart said. “You don’t really feel anything.”

Sean Reid-Foley earned the win after pitching a scoreless sixth in relief of Sean Manaea, who allowed one run in five innings. But it was Stewart who may as well have been credited with it.

It has been a turbulent five-week stretch for Stewart, who flew north with the Mets at the end of Spring Training despite not having a firm grip on a roster spot. So noncommittal were the Mets that they left open the possibility of an 11th-hour trade acquisition or waiver claim to replace Stewart on the roster -- a process that the veteran slugger called “difficult.” They were honest with him about the situation. It didn’t make things any easier.

Even after Stewart officially made the team, the specter of Martinez loomed over him. Though a back injury slowed Martinez’s Minor League progression, his arrival in Flushing was inevitable. As the day approached, reporters continually asked Stewart for his thoughts on the situation.

“I’m not going to lie and say it wasn’t [difficult],” said Stewart, who produced an .840 OPS over 58 games in 2023. “I know what I did last year, but that’s last year. It’s in the past. I know what I’m capable of. And I really wanted to be a part of it and help this team. Obviously, J.D. makes this team way better, but I think I can do that as well in the situations and the times that I get opportunities.”

When the Mets made their decision to keep Stewart, team officials cited the usefulness that he could provide. Although Martinez was due to receive the lion’s share of reps at designated hitter, the Mets set forth a plan to give the 36-year-old regular rest at the outset of his tenure. That left DH opportunities available for Stewart, who can also fill in at first base and right field.

“We will continue to find ways to get him in the lineup,” Mendoza said. “He’s always going to be ready for that crucial at-bat.”

With his spot secured at least for now, Stewart no longer feels as much stress as he did a fortnight ago. So tightly wound was Stewart that at one point early in the season, Mendoza approached him and said simply: “Smile.” It has become enough of a private joke between the two men that when Stewart hit his home run Tuesday, he made sure to look back at the dugout, find Mendoza’s eyes and grin.

“I’m very proud, but I know I can do better,” Stewart said. “I hold myself to a high standard -- higher than a lot of people. But I’m just glad to contribute in that situation and help the team win.”