Mets blow five-run lead as bullpen crumbles in loss to Astros

If Friday’s win and postgame concert provided an unmistakable nightclub vibe, the Mets’ matinee follow-up was shaping up to be more akin to a summertime block party.

But the rollicking run and good times were at least temporarily interrupted Saturday.

Tylor Megill and a shortened bullpen flushed a five-run lead — and a chance to take over the third wild-card position in the National League — with a 9-6 giveaway loss to the Astros that snapped a four-game winning streak.

Megill was optioned to Triple-A Syracuse following the game in an effort to get a reinforcement for the depleted bullpen, according to MLB.com.

Entrusted in the eighth inning with a 6-4 advantage — which had been 6-1 earlier in the game — relievers Jake Diekman and Reed Garrett combined to walk four and allow three runs, including Alex Bregman’s go-ahead two-run single with two outs.

“Four walks in that inning, they’re gonna make you pay eventually, especially facing a team like that,” manager Carlos Mendoza said. “Those guys have gotten big outs for us in the past and they’re gonna continue to get opportunities. … But it wasn’t the case today.”

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While it marked only the Mets’ fifth loss in their past 21 games, another win would have vaulted them over the Cardinals into a playoff position.

It leaves them 40-40 entering the 81-game midpoint of the regular season in Sunday’s series finale.

Still, referring to the team’s recent hot streak, Mets owner Steve Cohen posted on X before the game that “there is something special happening” at Citi Field.

“The players have come together and are playing for each other. The atmosphere is electric,” he added. “Let’s keep this going!”

In late May, with the Mets in the throes of what would turn out to be a 24-35 start, Cohen posted on X about the “mind-boggling” and “disheartening” stretch that threatened to torpedo the team’s season before it was two months old.

Cohen fully expected the team to be competitive this season, but the Mets initially could not overcome an injury to starting pitcher Kodai Senga and poor starts by several lineup regulars and Edwin Diaz, who missed all of last season due to knee surgery.

Mets fans clearly have embraced the resurgent squad in recent weeks, as well as the good vibes surrounding the McDonald’s character Grimace throwing out the first pitch earlier this month and the appropriately titled song “OMG” by veteran infielder Jose Iglesias, aka Candelita, which he performed on the field following Friday’s win.

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They left the ballpark Saturday with a different kind of grimace.

Houston scored first against Megill on Jake Meyers’ one-out solo shot in the second.

But the Mets responded with five runs in the bottom half against two-time All-Star lefty Framber Valdez on run-scoring hits by Iglesias, Harrison Bader and Brandon Nimmo and a two-run single by Pete Alonso.

Mark Vientos extended the lead to 6-1 with his fifth homer in eight games in the third inning, but the Astros got to Megill for three in the fourth, including a two-run double on an 0-2 pitch by Jeremy Pena.

Megill fanned Yainer Diaz and Meyers with two runners aboard to complete the fifth with the 6-4 lead intact.

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“Wasn’t terrible, but just hung an 0-2 breaker to Pena there,” said Megill, who lasted just three innings in his previous start. “Our job is to go deeper into games and save the bullpen arms.”

Especially with Diaz presently suspended for sticky stuff and with Drew Smith facing possible Tommy John surgery.

Diekman walked the first two batters he faced in the eighth, and Garrett walked Trey Cabbage to load the bases after the umpires lost track of the count.

After one run scored on a wild pitch, Jose Altuve also was walked before Bregman recovered from an 0-2 count for a full-count single to put the Mets in a 7-6 hole from which they would not recover.

Mauricio Dubon added a two-run double against Danny Young in the ninth.

“I obviously want a couple back. I didn’t execute to the best of my abilities,” Diekman said. “I was competing with everything I got out there and it just didn’t fall my way.

“Sometimes that’s how it is. It stinks. I didn’t execute my job at the end, and just didn’t put them away.”

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