There was a paltry crowd at Citi Field on Monday night, thanks due to bad weather and a bad Mets team.

And then they got to see what the Mets have done so often this year: lose.

The Mets took a one-run lead into the eighth inning, but Trevor Gott allowed a game-tying homer to ex-Met Tommy Pham before Drew Smith gave up a go-ahead double to Ketel Marte with one out in the top of the ninth in a 4-3 loss.

In the ninth, Ronny Maurcio drew a leadoff walk against Paul Sewald. The slumping Brett Baty bunted Mauricio to second.

With pinch-hitter Daniel Vogelbach at the plate, Mauricio stole third without a throw.

Vogelbach — hitting for Jonathan Arauz, who had earlier replaced Mark Vientos at third base — struck out looking.

Omar Narvaez walked to bring up Brandon Nimmo.

After pinch-runner Tim Locastro swiped second, Nimmo flied out to end it.

It was the Mets’ fourth loss in five games, as they close out a miserable season against a series of teams competing for playoff spots.

Those dreams died long ago in Queens, as the Mets turned their focus to the future at the trade deadline.

“It’s a juggling act, trying to be fair ethically [to other teams], but also being fair to us and trying to get us as many looks at guys as we can,’’ manager Buck Showalter said of the team’s youth movement. “We’re gonna have some decisions to make between now and April.”

Mauricio continued to impress, as he gave the Mets their only lead with a two-run double in the fourth.

Arizona entered having won four of its last five, but after the start of the game was delayed by over an hour due to inclement weather, Jose Quintana held them down for most of his five innings.

The lefty was effective for the ninth time in his 10 starts since returning from a fractured rib.

Quintana faltered in the top of the fourth, when he allowed two runs, sparked by a leadoff double from Pham.

The Mets answered with three runs in the bottom of the inning.

Jeff McNeil got them going with a one-out solo homer, his eighth of the year.

Pete Alonso and DJ Stewart followed with walks and Mauricio drove both of them in with a double to the gap in right-center.

It was Mauricio’s first extra-base hit since his 117 mph double in his first major league at-bat.

Quintana was replaced by Sean Reid-Foley, who tossed a scoreless sixth and Brooks Raley did the same in the seventh.

Gott faltered in the eighth, as did Smith in the ninth.

“This time of year, facing teams that are playing for something is good for us,’’ Quintana said. “We need to show something to play against teams in the race.”