If the Mets had regrets about cutting Travis d’Arnaud loose earlier this year, the Yankees no doubt wish he was still in Queens, as well, after the ex-Met dominated them Monday, finishing them off with a go-ahead, three-run homer off Aroldis Chapman in the top of the ninth.

The home run, d’Arnaud’s third of the night, gave the Rays the lead and the Yankees failed to rally in the bottom of the inning and lost, 5-4 to open a key four-game series in The Bronx.

“They’ve got a very good team,’’ Aaron Boone said.

The Yankees have now dropped three in a row to Tampa Bay and have seen their advantage in the division drop from 8 ½ games to five since July 6.

“Tonight was a great game in a lot of ways,’’ Boone said. “It didn’t end the way we wanted. They have a lot of guys [who] make it tough on you.”

On Monday, no one was tougher on the Yankees than d’Arnaud.

After Chapman gave up singles to Kevin Kiermaier and Guillermo Heredia to start the top of the ninth, he recovered with a pair of strikeouts.

That brought up d’Arnaud, who had already hit two solo homers off James Paxton earlier in the game — and hit a walk-off homer off Chad Green — to beat the Yankees earlier this month.

Chapman got ahead of d’Arnaud, 1-2, but d’Arnaud fouled off two 100 mph fastballs and laid off a pair of sliders in the dirt before Chapman left one up that d’Arnaud drove to right field.

Aaron Judge leaped for the ball, but it landed several rows into the short porch in right.

“I saw [Chapman] react to it as if he thought it was a fly ball,’’ Boone said. “But obviously here, that’ll get you.’’

“The way he hit that ball, I thought we had a chance to catch it, but that’s not the case,’’ Chapman said through an interpreter.

And neither Boone nor Chapman second-guessed throwing a slider in the situation.

“All night, the slider had been working for me,’’ Chapman said. “I tried it down and away and threw it higher than I wanted and he took advantage of it.”

D’Arnaud called himself “lucky” on the last shot, but that doesn’t describe the Rays, who are trying to stay in the Yankees’ rearview mirror.

“They’re real,’’ Boone said of Tampa Bay before the game. “I view them as one of the best teams in the league, one of the best teams in the game, for that matter.’’

A game-tying homer by Gio Urshela in the seventh and then a go-ahead two-run shot by Edwin Encarnacion in the eighth had the Yankees in prime position to come away with another victory.

Instead, they fell to 49-1 this season when leading after eight innings.

“I thought we did a great job of making their pitchers earn everything,’’ Boone said of his team, which knocked Blake Snell out of the game after five innings after he was forced to throw 93 pitches.

The Yankees got to Tampa Bay’s bullpen and hit three homers after going deep just once in their first three games since the All-Star break.

“It looked like we were gonna outlast them there. It’s a really good team,’’ the manager said. “They picked themselves off the mat when we had our way against them [earlier in the season].”

Any hope for another rally ended in the bottom of the ninth.

Judge walked with two outs, but Luke Voit struck out looking against Oliver Drake for the final out.

The finish wasted another solid outing by Paxton. The lefty allowed just two runs in six innings in his third straight good start, but the Yankees have lost all three of those games.