5 backup plans the Mets need to pursue if Pete Alonso is no longer an option

For much of the offseason, Pete Alonso re-signing with the New York Mets felt inevitable, especially when he reportedly expressed a willingness to take a short-term, high-AAV deal to stay with the team. Now, according to the latest report from SNY's Andy Martino, an Alonso reunion is anything but a formality.

The Mets have not ruled themselves out of re-signing Alonso, but according to Martino, consider it likely that he will end up elsewhere and that the team has pivoted to its Plan B.

If the Mets are officially resigned to Alonso landing elsewhere (they should not be), then things get tricky. They could choose to roll with what they have and allow a guy like Luisangel Acuña, Brett Baty, or even Ronny Mauricio at third base and move Mark Vientos across the diamond, but that's a hard sell for a team trying to win the World Series.

If Alonso departs, the Mets must bring in an external option to fill their corner infield need with any of these potential fallbacks making sense.

For more news and rumors, check out MLB Insider Robert Murray’s work on The Baseball Insiders podcast, subscribe to The Moonshot, our weekly MLB newsletter, and join the discord to get the inside scoop between now and the MLB offseason.

5. Alex Bregman is not as seamless of a fit as he might seem on paper

If the Mets let Alonso go, Alex Bregman is probably the most player most fans will turn to. The Mets can sign him to play third base, shifting Vientos to first. Their defense would improve and they'd be adding a player with more postseason experience than just about any active player. With that being said, though, it's tough to envision this happening for a couple of reasons.

First, Bregman, unlike Alonso, is reportedly unwilling to accept a short-term deal. Now, that could change as the offseason continues to progress, but why would the Mets let Alonso walk only to sign Bregman to a long-term deal?

Second, Bregman is coming off his worst season. He slashed .260/.315/.453 with 26 home runs and 75 RBI. Bregman is obviously the better defender, but his bat, outside of his MVP-caliber 2019 season, has never come close to matching that of Alonso's from a power standpoint. The Mets have table-setters, they need big boppers to hit behind the star duo of Francisco Lindor and Juan Soto. Bregman has some power, but not close to Alonso's.

This comes down to whether the Mets, after passing on a short-term deal with Alonso, would be willing to give Bregman, a player who is nine months older than Alonso, a long-term commitment coming off his worst year while also coughing up draft pick compensation. It's really tough to envision the answer to that being a yes.

4. The Mets should bring Jose Iglesias back whether they re-sign Pete Alonso or not

Jose Iglesias was one of the 2024 Mets MVP's thanks in large part to what he was able to do off the field and in the clubhouse, but what Iglesias was able to do on the field cannot be ignored either.

The 35-year-old slashed .337/.381/.448 in the regular season with four home runs and 26 RBI in 85 games played, flashing an elite glove and a clutch gene at the plate. His production waned in October, and his .382 BAbip from this past season suggests that he'll have a difficult time replicating his regular season production, but regardless, he's a player that the Mets should bring back whether Alonso returns or not.

This team could use a backup infielder in general, and Iglesias can see increased reps at the hot corner if Alonso walks. The fans love him, the players love him, he was a productive hitter and defender, there's no reason not to bring him back.

3. The Mets need Anthony Santander's bat badly enough to ignore his subpar positional fit

There are a couple of major drawbacks to consider with Anthony Santander. First, he has the qualifying offer attached, meaning that the Mets would have to forfeit two additional draft picks to sign him, as they did with Soto earlier this offseason. Second, he has just 13 games of experience at first base in his eight-year career. He played just one inning at that position in 2024.

Would the Mets be willing to part with more draft picks for a player who is relatively unfamiliar with the position? That's a question that only they can answer.

If the Mets do let Alonso go, though, this almost has to be considered, as Santander's bat is the only one on the open market that can replicate what Alonso can do. Santander set career-highs this past season with 44 home runs and 102 RBI. He doesn't get on base a ton, but it's not as if Alonso is known for that skill set, either.

The fit is far from perfect, but if Alonso walks, the Mets need a big bat to stick into the middle of their order. Santander, like Alonso, is reportedly open to a short-term deal. I'm not sure why they'd be willing to sign Santander and not Alonso, but if Alonso walks, Santander must be considered.

2. The Mets could be the Nolan Arenado suitor the Cardinals have been waiting for

All offseason, the St. Louis Cardinals have been searching for a Nolan Arenado suitor. Well, if Pete Alonso leaves, the Mets might be that suitor.

St. Louis' goal with an Arenado trade could not be clearer. They're trying to save as much money as they possibly can. Well, the Mets are a team that would conceivably be willing to take on something similar to the $45 million over three seasons that the Houston Astros were reportedly willing to take on before Arenado vetoed a trade that would've sent him there.

Arenado is nowhere near the hitter he once was, but he's still a Gold Glove-caliber defender, as he ranked in the 95th percentile in OAA this past season according to Baseball Savant. Plus, with more talent around him, there's reason to believe Arenado's production could tick up a bit from where it ended up in 2024.

Arenado would cost virtually nothing prospect-wise and would be a lot cheaper than Alonso while providing excellent defense and a bat with some potential upside. A left side of the infield featuring Arenado and Francisco Lindor would be a treat to watch. If Alonso leaves, an argument can easily be made that Arenado is the most realistic fallback option.

1. A Vladimir Guerrero Jr. trade is the dream Pete Alonso backup plan

Let me be abundantly clear. This almost certainly is not happening. The Toronto Blue Jays have shown no willingness to even consider trading Vladimir Guerrero Jr. (whether that's right or wrong), and are trying to extend him as we speak. It'd make little sense for the Jays to trade him shortly after spending over $30 million on a reliever. With that being said, though, what if the extension talks fail to pick up any steam? What if the Mets offer a package that is too good for Ross Atkins and Co. to pass on? Without an extension, a Guerrero trade can't fully be ruled out, and would be the dream Mets scenario.

The Mets have been hesitant to pay Alonso, but there's reason to believe they'd be more than willing to give Guerrero a monster offer. Yes, he's a first baseman like Alonso, but he's also five years younger. He fits into the age range David Stearns is willing to go head over heels for.

Guerrero is just 25 years old. Soto, a player Stearns and Steve Cohen gave the richest contract to in professional sports history, is 26 years old. Yoshinobu Yamamoto, a pitcher that the Mets were willing to make the richest in MLB history before even throwing a single pitch at the highest level, was just 25 at the time. Guerrero is not even in his prime yet, so it absolutely is conceivable to believe that the Mets would be willing to trade a monster haul and extend him.

A Guerrero trade is the one scenario where the Mets would get better by letting Alonso walk. It's extremely unrealistic, but is something that the Mets are going to have to push hard for if Alonso departs.