Mets’ Mark Vientos, Brett Baty ready to potentially play first base

If the Mets are truly going to move on from Pete Alonso, it may have ramifications for Mark Vientos and Brett Baty.

The pair of young Mets believe they are up for the challenge.

Both natural third basemen were instructed by the Mets earlier this month to mix in defensive work at first base, The Post’s Joel Sherman first reported on Friday, a sign the club has begun to prepare for life without Alonso.

As long as Alonso remains a free agent, a path back to the Mets remains possible — even with Steve Cohen throwing cold water on the state of negotiations — but in the meantime Vientos and Baty are trying to make themselves in-house options to step into Polar Bear-sized shoes at first base.

“It’s hard not to pay attention to it when you see it on every platform,” Vientos said of the noise surrounding Alonso, whose absence loomed large at Saturday’s fan fest at Citi Field. “I’ve been getting ready for anything that happens. At the end of the day, you gotta go out there and play. I’m ready to do whatever it takes.”

Even if it’s across the diamond from his regular position.

“I love playing third base, but right now, my main focus is what can I do for us to get to the World Series and win a championship?” said Vientos, whose offensive emergence last season played a key role in the Mets reaching the NLCS. “That’s what I want.”

While Vientos has played 84 games at first base as a pro (70 in the minors and 14 in the majors), Baty has not played there since he was a sophomore in high school.

But the Mets are trying to give themselves options on the two corner infield spots heading into spring training, barring further roster moves.

Baty said president of baseball operations David Stearns reached out to him “a couple weeks ago” and asked him to start taking reps “all over the infield, first base included.”

So the 25-year-old, who had added second base to his repertoire last year at Triple-A, immediately overnighted a first base mitt and began using it the next day during his workouts back home in Texas.

“[First base] is still pretty new to me, so I’m still trying to figure it out,” said Baty, sporting his new No. 7 after giving up No. 22 to Juan Soto for an undisclosed return. “I think the ground balls are going to come simple, just like third base or second base. I think it’s going to be the footwork, just receiving throws.”

Manager Carlos Mendoza on Saturday declined to say who would be his starting first baseman from the roster as it is currently constructed, two weeks before spring training begins, but insisted the Mets had options at both corners.

Mendoza cited Jared Young and non-roster invitee Joey Meneses as additional options at first base while the third base mix (if Vientos were to take over first base) could include Baty, Luisangel Acuña (whom the Mets have told to get reps at the position) and Ronny Mauricio.

“We keep saying it, our young players are going to get opportunities,” Mendoza said.

Vientos finally got his opportunity last season, after not making the roster out of camp, and made the most of it.

While posting an .837 OPS with 27 home runs, he became an integral part of the top half of the lineup and believes he can carry that success over into 2025, whatever position he is playing.

“I’m very confident, for sure,” Vientos said. “I’m excited to get back. I want to get back to the same spot we were in last year. It was so much fun just to be in that environment, the playoffs and playing here in front of the best fans in the game. Just want to experience that again.”