Mets’ post-Pete Alonso first base plan keeps looking worse: ‘Made it a weakness’

The early returns have been perhaps worse than anyone could have imagined.

Jorge Polanco, signed to a two-year, $40 million contract with the hopes that he could transition from the middle of the infield to first base, has been hurt most of the season and played poorly when on the field.

Brett Baty, introduced to the position during spring training, has been inconsistent in the field and at the plate. He’s shown flashes of his lefty power, but also entered Wednesday in an 0-for-10 skid.

And then there’s Mark Vientos, who has struggled badly on both sides of the ball, looking to recapture at least the power he displayed two years ago, which seems to be more and more of a distant memory.

Mets third baseman Mark Vientos (27) falls off the bag, allowing a batter on during the ninth inning when the New York Mets played the Minnesota Twins on Wednesday, April 22, 2026. Robert Sabo for NY Post

Altogether, they have the fourth-worst OPS at the position this season (.581), a year after Pete Alonso helped them to the second-best OPS in the majors (.861).

Neither has stood out defensively, either.

And according to FanGraphs, the group has the second-lowest WAR (-0.5).

Asked about the spot before Wednesday’s game against Washington at Citi Field, Carlos Mendoza said the duo of Baty and Vientos has “handled the position fine,” adding Vientos has been OK defensively.

But the manager acknowledged: “Offensively, we expect more.”

In fairness, the lack of production has been a failure of almost the entire lineup and not just at first base.

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But it’s felt there especially, given the importance in the lineup, and because they had such a consistent threat at first as long as Alonso was around.

Jorge Polanco (11) throws out Pittsburgh Pirates first baseman Ryan O’Hearn at first base during the seventh inning of a baseball game. AP

“They took a strength and made it a weakness,’’ one National League scout said. “I think Baty can hit, but he shouldn’t be at first base. If they had just kept him at third, where he looked comfortable last year, I think he would have come on at the plate. But they’re making it harder on him, all to get another guy who’s out of position [former shortstop Bo Bichette] into the lineup.”

With Polanco nursing both a right wrist contusion and Achilles discomfort — and considered week to week by David Stearns — the Mets figure to go with Baty and Vientos.

“We signed Polanco to play there and he’s had health issues,’’ Mendoza said.

Pete Alonso of the Baltimore Orioles blows on his finger gun as he rounds the bases after hitting a two-run home run. Getty Images

Asked who else could play first base, Mendoza said MJ Melendez was capable of seeing time there, as well as Luis Torrens in an emergency.

Ryan Clifford, ranked the organization’s fourth-best prospect according to MLB Pipeline, is splitting time between first base and the corner outfield spots at Triple-A Syracuse and has five homers in his previous nine games.

The 22-year-old doesn’t figure to be the answer, at least in the short term.

And with Francisco Lindor’s absence — out indefinitely with a strained left calf — decimating the offense, the hole at first base looks even worse.

Mets third baseman Brett Baty (7) fields a throw during the first inning when the New York Mets played the Pittsburgh Pirates. Robert Sabo for NY Post

The only bright spot for the Mets, if you want to call it that, is that Alonso still hasn’t begun to hit consistently in Baltimore after he left Queens for a five-year, $155 million contract.

That won’t help the Mets get out of their current predicament, and they have little choice but to keep rolling with Baty and Vientos.