Billy Eppler walked into the Citi Field press conference room Sunday afternoon midway through Buck Showalter’s standard pregame media briefing and took a seat in the back row.

There was nothing standard about that.

Either was Showalter soon after announcing his own firing. He did not use that word “firing,” nor did the Mets in their press release. But this was an axing and it was orchestrated not by Eppler, though he gave a nod to Showalter that it was fine to go ahead and make the announcement. It was not even the act of Cohen, who in a press gathering after the Mets’ season finale confirmed that once he hired David Stearns as president of baseball operations early last month, it was understood that Showalter would not be back — just the how and when remained.

So Showalter was fired by a man who was not in the building. He was fired by a man who he still has never met or talked to, thus, that person has never explained face-to-face to Showalter why he will no longer be the Mets’ manager.

This was a hit job in the classic way — ordered by someone who was not present at its execution. It was the first act of the Stearns administration, issuing a key decision before he officially is announced as Mets president of baseball operations on Monday.

Of course, Cohen — the ultimate Mets authority — has the final say. But just as “of course” is that Stearns was not coming (not even for Cohen’s largesse) without authority over the major league team, including the manager. And I have yet to talk to anyone in the last few weeks who knows Stearns who believed he would retain Showalter, who has a year left on his contract.

Mainly because if you asked what is the 180-degree opposite of Stearns, Showalter would be a logical response. Stearns is a New Yorker. Tight-lipped. And not a fan of the baseball power flowing from anywhere but the person in his chair. Showalter — even with Yankees and Mets stints — remains folksy and chatty and a manager who will challenge the new orthodoxy and use his own networks to gather information.

The major league manager more than anyone else is the organizational spokesperson. Stearns clearly thought it was vital to have someone he trusts to stay on his message. And he was willing to add a managerial search to an already overflowing to-do list that includes what to do with Pete Alonso and determining whether the Mets should be big players for Shohei Ohtani in free agency and/or Juan Soto in trade.

“It became clear that [Stearns] wanted to go in a different direction,” Cohen said.

Perhaps, this will be easy. The Mets wait out the Brewers postseason and hire Stearns’ longtime Milwaukee skipper, Craig Counsell, whose contract is expiring. But that is potentially a dangerous game. The Brewers are in the playoffs and if there is no wink-wink rule-breaking behind-the-scenes understanding between Stearns and Counsell, then what happens if Milwaukee has an extended playoff run (Game 7 of the World Series is Nov. 4) and then Counsell stays with the Brewers, gets a job elsewhere or decides not to manage in 2024?

If not Counsell, would Stearns consider someone without managerial experience for this difficult role? Or does he inquire instead on Bob Melvin (he is not expected back with San Diego), or coaches like Don Mattingly, Ron Washington and Walt Weiss?

As perilous and arduous as a managerial search might be, Stearns clearly decided he could not stick with Showalter, who indicated he would still like to manage, but at 67 and having managed five teams already that is tenuous at best. If this is it, he finishes with the second-most games ever managed (3,393) without ever winning a pennant (Gene Mauch had 3,942). His last best chance came with the 101-win 2022 Mets. This year’s club was supposed to build on that with Cohen authorizing a record payroll that swelled toward $500 million with the luxury-tax penalties included.

Instead, these Mets were a disappointing fourth-place outfit. Neither Cohen nor the players held Showalter responsible — the veterans, in particular, liked playing for him. But after Saturday’s game, Eppler let Showalter know he would not be back and asked how he wanted to handle it. Showalter decided to complete the season and announce his fate before the finale.

Showalter had been positively talking up what the Mets have coming from their farm system and the overall near future — sounding very much like a guy who couldn’t wait to be part of it — before getting Eppler’s nod and choking up as among other items, he said, “Steve and Billy, they’ve got good leadership and good ownership here, and they’ve got a perfect right to go in a different direction.”

But Showalter’s fight against tears was not due to Steve or Billy. It was David, whose first major act running Mets baseball operations was to take down a managing Goliath.