NEW YORK — After mastering the art of booing from more than a month’s worth of steady practice, the New York Mets fans at Citi Field stood and cheered plenty Tuesday night because of A.J. Ewing.

Before Ewing’s first plate appearance, fans gave him a standing ovation. They applauded each of his three, yes, three walks. They celebrated his stolen base. They went wild for his first hit, a triple.

“He was pretty much perfect at the plate today,” Mets manager Carlos Mendoza said after New York’s 10-2 win over the Detroit Tigers.

The common sentiment from executives, scouts and agents across the league following news of Ewing’s promotion to the big leagues a night earlier sounded considerably less enthused: The Mets reek of desperation.

Ewing, 21, played in just 12 games at Triple A. Sometimes, a player is so good that he skips Triple A entirely. Detroit shortstop Kevin McGonigle is an example. Ewing is a top-100 prospect. He projects well. His outlook, however, does not paint him as the next McGonigle, who entered the season as the consensus top prospect in the American League and already ranks inside the top 25 in fWAR (1.5).

So, yeah, the Mets are desperate. And they should be. They are 16-25, jockeying daily to avoid being baseball’s worst team.

For as desperate a move as it was, calling up Ewing to play center field on an everyday basis was also necessary. He was the best option. Says a lot about him. Says more about the state of the Mets.

Even before catcher Francisco Alvarez left the game with a right knee injury (set for imaging on Wednesday), the latest rundown regarding the trio of Mets lineup regulars on the injured list was ominous.

• Shortstop Francisco Lindor (calf) is set for an MRI this week, most likely on Wednesday. The Mets hope the exam will finally provide clarity on a timetable for a return. Lindor is no longer wearing a boot, but the Mets know better at this point than to get ahead of themselves in expecting good news.

• There is no guess for when Jorge Polanco (Achilles) is back. He has good days and bad days and not enough consistent days in between to know. At least Polanco took batting practice on Tuesday (one of the good days, according to Mets officials).

• Then there’s Luis Robert Jr. (back), the player Ewing is essentially replacing. Robert’s situation is the murkiest of them all. His back soreness has not resolved. He is seeing specialists. He is not progressing as the Mets had hoped.

The Mets acquired Polanco and Robert during their transformative offseason. Before joining the Mets, neither player stood out as a symbol of health. Of the group of homegrown players the Mets moved on from over the offseason, availability was always a calling card. In going a different way, Mets president of baseball operations David Stearns took on short-term situations; many times, the kind of players who present short-term fixes also carry health risks.

“We absolutely have to look at our risk assessment on injured players or players who get injured once they’re here,” Stearns said. “We know we are taking a level of risk when we bring players in with injury histories.

“We are feeling that risk right now, and it hasn’t helped that a number of our players have gotten hurt at the exact same time. It’s not something we necessarily anticipated. But I think that’s a fair question and something we need to look at.”

At other points during Stearns’ news conference on Tuesday, he said he wasn’t ready to issue a postmortem on his club’s season and that he hadn’t yet thought of selling ahead of the Aug. 3 trade deadline. It’s not even the midpoint of May. This is life in the Mets’ world.

Considering their downtrodden offense and lack of alternatives, there wasn’t much of a choice other than to call up Ewing. The Mets needed something.

The Mets — who scored more than two runs on Tuesday for just the 23rd time this season — simply could no longer use a lineup containing so many journeymen. A trade at this juncture is unlikely; finding a match in May under an expanded playoff format is incredibly rare. The Mets could’ve called up outfielder Nick Morabito, who is on the 40-man roster. But although Morabito is off to a fine start in Triple A, he does not carry the projection that Ewing does. The Mets wanted impact.

The reality is, Ewing and his dozen games of Triple-A experience are better than a handful of players the Mets use on an everyday basis. Pro evaluators said as much.

“It’s a well-rounded game,” Mets senior vice president for player development Andy Green said. “It’s an ability to impact in all areas of the game.”

Mets people suggest that, at minimum, Ewing’s speed and defense should boost energy. They are hopeful for more. In Ewing, they see someone who makes good decisions in the batter’s box, hits balls hard all over the field and fares well against all kinds of pitches.

That includes fastballs, an issue that wasn’t always the case. In a trying 2024, Ewing struggled against fastballs. Two years ago, as one of Mets hitting coordinator Daniel Nicolaisen’s first pupils, Ewing adjusted his swing and approach and started to improve. Confidence followed.

Toward the end of the 2024 minor-league season, Green told Ewing that he was going to start the next season where he was just finishing up, in Low A.

Ewing responded, “That’s fine. I won’t be here long.”

Ewing, of course, wasn’t. Over the past two years, he has maintained a batting average over .300. Everywhere he goes, he hits and gets on base. It’s been a while since he faced adversity. It is unknown how he will handle it once it inevitably occurs in the major leagues.

With Ewing, some Mets people hold cautious optimism that he can get off to a fast start. That is different than some other prospects. They like his approach when it comes to discerning which pitches to swing at. And they believe his swing is simple. His first day on the job supported such a theory.

In his first plate appearance, Ewing was not jumpy. Against Jack Flaherty, he took a couple of good pitches for balls and worked a seven-pitch walk to load the bases and help build a run. With runners on base, he did not try to do too much.

“That’s part of my identity as a hitter,” Ewing said.

During the final moments of the blowout Tuesday, Mets fans from a remaining sparse crowd — the score, weather and the Mets are all factors there — offered a faint, rhythmic “A-J-Ew-ing” chant. Austin Warren was on the mound for the Mets. Just a couple of weeks ago, when the Mets were on the other side of a lopsided game, their fans sarcastically chanted “M-V-P” for Warren. This time, the vibe was different. The vibes were … good.

Who knows how long they’ll last? The elusiveness of anything good for the Mets in 2026 is partially why Ewing is here. Calling him up now was desperate, necessary and right.