Mets’ dreadful play continues with ugly loss to lowly A’s as skid hits four

The road trip from hell has ended, but the Mets brought their hellish skid home with them.

Carlos Mendoza’s crew had built-in excuses over a 10-games-in-10-days, four-city voyage that ended with three smackdowns in Seattle.

They had no such alibi on Tuesday when they began an important, nine-game homestand with the kind of faceplant that Pete Alonso experienced in the sixth inning.

A 9-4, series-opening loss to the AL West-worst A’s in front of 31,923 at Citi Field meant the Mets have been outscored 31-5 over this four-game losing streak in which their hitting has not done enough and their pitching has been destroyed.

Paul Blackburn took the baton from his battered rotation mates and continued the trend.

In his third start with the Mets, he was booed in his home debut against the club that dealt him at the end of July.

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“Command on all of his pitches,” Mendoza said of what went wrong, which included a game-opening, five-pitch walk to begin a three-run first. “It was a weird outing for him. … First batter of the game, some of the misses were just kind of weird.”

Blackburn, excellent in his first two tries with the Mets, was lit up for seven runs (six earned) in four innings in which he dug a hole too deep to escape.

His night started poorly and didn’t get much better.

He loaded the bases in the first and watched Seth Brown drill a double into right-center that cleared those bases.

“Obviously tough road trip we were on,” said Blackburn, who said he had no pitch he could lean on this time. “I was hoping to come in here and go out there and get through the first [inning] quickly, give the guys a chance on the offensive side.

“It just didn’t work out tonight.”

During this four-game funk, Jose Quintana, Sean Manaea, Luis Severino and now Blackburn have allowed 19 runs in 18 ²/₃ innings.

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The Mets are down Kodai Senga and Christian Scott , with Blackburn — who served up a three-run homer to Shea Langeliers (4-for-4) in the third inning that put them in a 7-1 hole — their only starting-pitcher addition at the deadline.

“They’re going through it,” Mendoza said of his struggling rotation. “Our starters are not getting length, and then we’re getting behind early in games, and then we’re having a hard time getting back. … It’s part of the 162-[game season] because they’ve been so good for us.”

There probably should be some qualms about the Mets rotation and struggling offense.

There should not be any qualms about the effort level of the Mets (61-58).

Down by six runs after four innings, they got within an arm’s reach in the fifth, when Jesse Winker’s RBI double and Alonso’s two-run single restored some hope.

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Three times they brought the tying run to the plate, but reliever Austin Adams — a Met in spring training who was dealt to Oakland — was overpowering in retiring Jeff McNeil, Jose Iglesias and Francisco Alvarez.

After Alvarez struck out, an animated Adams dramatically raised his arms and imitated the Mets’ “OMG” celebration, which will set up an interesting dynamic for the rest of the series.

The Mets were still battling and increasingly bruised in the sixth, when Alonso made a remarkable stop and paid for it.

A ground ball down the first-base line from Miguel Andujar had beaten him — but Alonso angled his dive and reached behind him to successfully knock the ball down.

An off-kilter body shifted its weight from stomach to face, his nose scraping against the dirt and Alonso rising with a bloody nose — and rising to throw home a bit too late to prevent another A’s run from scoring.

The A’s scored twice in the frame in a rare game in which Jose Butto (two runs on seven base runners in two innings) was knocked around.

“I thought he made a really good play keeping the ball in the infield,” said Mendoza, who added Alonso took a “pretty good” bruise on the dive but he would be OK.

After their explosion to start the fifth inning, the Mets couldn’t scratch across a run against a quality Oakland bullpen that held them to two hits in five innings.

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