Mark Leiter Jr. is a middle reliever. Regardless of how this season went, barring an unforeseen breakthrough, he was going to make his money in the fifth and sixth innings. After being acquired at the 2024
trade deadline for Jack Neely and Ben Cowles, he struggled mightily, giving up an unsustainable amount of barrels and turning into an overall flop.
He had an opportunity to change the narrative going into 2025, and although he suppressed the amount of barrels he allowed quite significantly, it turned into another rough season. Despite good stretches at times and good peripherals, Leiter Jr. would find himself in jam after jam and quickly became unusable in the second half of the season, to the point where he was left off the playoff roster and is currently a likely non-tender candidate.
Grade: D-
2025 Statistics: 48.1 IP, 4.84 ERA (84 ERA+), 3.55 FIP, 10.1 K/9, 3.2 BB/9, 0.6 fWAR
2026 Contract Status: Arbitration (projected salary: $3 million)
Despite how his season went, there’s reason to think that he might be salvageable if Brian Cashman doesn’t eat his losses and non-tender him. His peripherals looked significantly better than his performance showed, but more on that later.
Leiter Jr. started the season with four strikeouts in two scoreless outings, but his third outing was an unmitigated disaster. After a pair of walks in an early April outing against the Diamondbacks loaded the bases in the eighth, he coughed up a go-ahead grand slam to Eugenio Suarez and wound up taking the loss:
After that game, he pitched well for the next two months. The 34-year-old Toms River native allowed just three runs in the next 21.1 innings through late May until a blowup outing at Chavez Ravine in the midst of a horrific 18-2 loss. He would start to slump after that, struggling in a June outing in Kansas City that forced Devin Williams in to close in a once-five-run game and then taking the loss on June 30th against the Blue Jays in an inning more known for bizarre defense than anything.
In between those outings, he took the loss when he was saddled with the impossible task of pitching for the Yankees in a road extra-innings game. With no offensive support, he went two-up in a losing effort on June 24th in Cincinnati after throwing 27 pitches the day before. That night, when trying to cover the bag on an eventual Elly De La Cruz infield single, he suffered a left fibular head stress fracture that he ultimately tried to pitch through before hitting the injured list in early July.
He returned on August 5th and had an opportunity to move up the pecking order in an extremely volatile bullpen, and while he didn’t pitch badly, his strikeouts were down, his walks were up, and he wasn’t generating the whiffs and chases that made him initially intriguing. From August 22nd to September 10th, he allowed runs in five out of six outings, including when he combined with Fernando Cruz for an inning from hell on September 9th against Detroit.
After four straight scoreless outings in low leverage to end the year, he did not pitch in October. He made the Wild Card Series roster, but was left off the ALDS roster entirely. It was a bad season for Leiter Jr., there’s no denying that. However, there’s a case to be made that he was one of the unluckiest relievers in the sport.
Despite an awful end to the season, Leiter Jr. was in the 92nd percentile in average exit velocity, 94th percentile in hard hit rate, and 88th percentile in barrel rate. When his struggles in 2024 were directly because of allowing too many barrels, that was a welcome sign.
For much of the season, he boasted elite whiff and ground ball rates, but those also declined as the season went on. He ultimately finished in the 77th and 74th percentiles respectively. When you look at his profile, it doesn’t look like a guy who struggled all season long.
So what happened? Well, he seems to have contracted the 2024 Clay Holmes virus when it came to BABIP. Of all relievers to throw at least 45 innings, Leiter Jr. had the second-highest BABIP (.374), trailing only Rays fireballer Mason Montgomery. For a guy who did not allow a lot of hard contact, that seems incomprehensible.
Leiter Jr. allowed 41 balls in play under 80 mph. On those 41 batted balls, 19 of them were hits for a .463 batting average. The major league average? .225.
It also doesn’t help that he had cartoonishly bad defense behind him. There were only three pitchers in baseball who had -10 OAA or worse behind him: Justin Verlander, Carlos Vargas, and Mark Leiter Jr.
On a rate basis, this is insanely bad. Accruing -12 OAA in 48.1 innings is baffling and, since OAA has been tracked, has never happened before. The only other pitcher to have an OAA that bad behind them in under 60 innings is 2023 Alex Young (53.2 IP). Two-thirds of that horrendous number is due to, funny enough, Anthony Volpe. Which leads to the following funny stat:
Anthony Volpe with Mark Leiter Jr. pitching: -8 OAA (48.1 IP)
Anthony Volpe with anyone else pitching: +1 OAA (1,255.1 IP)
Ignoring how that just shouldn’t be possible, what does this mean for Leiter? Is he an actual good pitcher that was beyond snakebitten?
I’m not quite sure. 2024 Clay Holmes was an unequivocally good pitcher who had some brutal blown saves and insanely bad luck. Leiter, on the other hand, grades out better than his numbers show, but not quite as good as Holmes did last year, especially after missing a month due to injury.
Leiter succeeded in 2024 with his splitter and curveball doing damage, making him one of the best strikeout relievers in the sport. He started 2025 with the same nastiness on those pitches, but they lost effectiveness over time. His whiff rate in 2024 was over 38 percent, but he spent the summer struggling to get it over 20 percent. His splitter was very inconsistent, as at times it looked like Cruz’s, but other times he struggled to throw strikes with it.
In a day and age where you can find solid middle relief for pennies on the dollar, it would make sense for Leiter to be non-tendered. $3 million isn’t nothing, after all. That said, I’m willing to bet that he’ll get better results next season if he’s able to fully rehab the leg injury that he probably didn’t let heal properly over the summer. It’s a gamble, but if he’s able to combine the nastiness of his secondaries in 2024 with his ability to limit hard contact in 2025, he can potentially be a piece in 2026.
