Marcus Semien’s Decline Continues as Mets Make Curious IL Move

Marcus Semien is headed to the injured list with a left hip flexor strain, but the timing of the Mets’ move is raising questions as the veteran second baseman continues a season-long decline on both sides of the ball.

Marcus Semien is heading to the IL: here's what it means for the Mets moving forward. | Kyle Ross-Imagn Images

Another injury has struck the Mets, this one coming abruptly, raising questions about its legitimacy. Less than 24 hours after making two errors at second base, Marcus Semien is set to hit the 10-day injured list with a left hip flexor strain, first reported by Chelsea Janes of SNY.

Mets are expected to place Marcus Semien on the injured list this afternoon, according to a person familiar with the situation.

— Chelsea Janes (@chelsea_janes) June 25, 2026

The move comes off as odd, as Semien was seemingly in zero pain or discomfort Wednesday night when speaking to the media.

“Just attention to detail,” Semien said in an interview with SNY on Wednesday. “It’s always going to be that with defense. The first step wasn’t great on the first one. It seems like when I pick up the ball and rush the throws aren’t good. It’s frustrating. Those are plays I want to make, plays I want to make tomorrow to help us win.”

Marcus Semien talks through his two errors today and why they happened: pic.twitter.com/S7kBTB60MT

— SNY Mets (@SNY_Mets) June 25, 2026

The proof is in the pudding. Semien mentions he wants to make the plays in the next game to help the team win, without mentioning any pain or discomfort. For the Mets, Semien has been a disappointment, as expected when the team acquired him last November.

IL placement is another example of Marcus Semien disappointing Mets fans

The Mets approached the Rangers in an attempt to offload the long-term contract of Brandon Nimmo, doing a one-for-one swap with Texas to acquire Semien and part ways with their longtime outfielder, who was clogging the major league roster from prospects like Carson Benge and A.J. Ewing. The move shaved $30.5 million off the books in New York, forcing the Mets to endure the contract of Semien for three more seasons, rather than sit with Nimmo for the next five. 

While President of Baseball Operations David Stearns preached that the move was intended to improve their "run prevention," the exact opposite has been the case.

Over the last 33 games alone, the 35-year-old has made six errors, having his worst defensive season in five years. In 2026, Semien held a minus-3 defensive run value along with minus-3 outs above average (OAA, per Baseball Savant); in 2025, his defensive value and OAA were plus-6, while he only committed two errors on the entire season. It was obvious the veteran was slowly declining in play, but once arriving in Queens, his career has seemingly taken a complete nosedive.

Offensively, his numbers are worse than ever, batting .214 as the Mets' everyday second baseman with nine HRs and 29 RBIs, along with a .613 OPS and .271 OBP, striking out 68 times, holding the highest K% of his career since 2017 at 21.4%. The worst stat is his batting run value, which is in the second percentile at minus-13, the sixth-worst in baseball.

The decision to move Nimmo isn’t what’s wrong here; it’s the fact that the only value they could find was Semien, who is 35 and declining in every aspect of the game. With Semien down, here is who could potentially take over at second base.

Mets second base option with Semien injured

The Mets will be promoting Ronny Mauricio, whom they reinstated and optioned to Triple-A after he completed his rehab assignment. Mauricio saw time as the Mets' starting shortstop when Francisco Lindor went down with a calf injury, batting .219 through 10 games with a home run and two RBIs, holding a .531 OPS. However, the injury bug would catch up to the Mets' former top prospect, hitting Mauricio with a fractured left thumb.

Ronny Mauricio will get another shot with the Mets as Marcus Semien misses time. | Vincent Carchietta-Imagn Images

Mauricio recently wrapped up his five-game rehab stint with the Syracuse Mets, going 7-for-19 with five RBIs and a .381 OBP. As always, New York’s younger players produce at the Triple-A level, but consistently fail to deliver in the major leagues. 

There will be options for the second base position while Semien sits with the hip injury.

For starters, the easy choice is to shift Bo Bichette to second while having Brett Baty play third, or vice versa. The question however is, does Baty deserve to be playing every single day?

The Mets have given Baty every opportunity to find rhythm at the major league level. Their former top prospect has appeared in 76 of their 80 games, batting just .217 with three HRs, 26 RBIs and a .602 OPS while striking out 73 times. At this point, it’s well known that the 26-year-old won’t blossom into a star at the MLB level, with his career role likely being a utility depth piece. 

What the Mets could do is turn to their switch-hitter, Mauricio, who really hasn't had the same amount of long-term opportunities as Baty. Whatever the Mets decide to do, it won’t save their season; they're already too far in the basement to make a miraculous comeback.