Mets catcher Francisco Alvarez left the field at American Family Field on Friday in great pain.

Like Francisco Lindor, who felt his back “strain” as he stepped onto second base two weeks ago, Alvarez also injured his back while running across the bases. In the 22-year-old’s case, he felt back spasms as he slid feet-first into third base.

As Alvarez reached third, he grabbed his back, rose to his knees and winced in pain. He then laid face down on the bag while the trainers came and began tending to him. After a few minutes, he was helped to his feet and carefully left the field while his teammates and coaches waited anxiously for him in the dugout.

After the game, Alvarez spoke to reporters and reported some promising news.

“I feel a lot better, I feel like my body is doing a lot better,” Alvarez said on SNY. “I just feel a little tense. Let’s see if I can play tomorrow.”

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Alvarez went hitless and had two hits on walks in the Mets’ 8-4 loss to the Brewers. He escaped the throw in the fourth inning after throwing a called strike that was clearly off the plate. At that point, he was visibly upset and exchanged a few words with home plate umpire Ramon De Jesus before Mets manager Carlos Mendoza came to the rescue.

It’s been an offseason for Alvarez, who led all NL catchers with 25 home runs last season. In 97 games, he is slashing .233/.306/.400 with 11 home runs and 44 RBIs.

Alvarez missed nearly two months earlier this year after breaking his thumb. He stressed that the thumb injury did not play a role in his attack, but over time his strength returned.

In his final 12 games, he batted .235 with a 1.022 OPS, including six extra-base hits (five home runs).