New York Yankees pitcher Mark Leiter Jr. (56) stands on the mound after Cincinnati Reds shortstop Elly De La Cruz (44) reaches third base on a wild pitch in the 11th inning of the MLB interleague game between the Cincinnati Reds and the New York Yankees at Great American Ball Park in downtown Cincinnati on Tuesday, June 24, 2025. The Reds won 5-4 in 11 innings. Sam Greene/The Enquirer / USA TODAY NETWORK via Imagn Images

Surprising Reason Behind Yankees Reliever's Struggles

Originally posted on New York Yankees on SI
By Jack Markowski | Last updated Jul 5, 2025 9:00 AM ET

After a strong start to the season, New York Yankees right-handed reliever Mark Leiter Jr. has seen his numbers tumble amidst a prolonged rough patch.

Over his past seven outings, Leiter has posted an unsightly 8.44 ERA and 2.44 WHIP. Remarkably, however, both of those stats are actually heading in the right direction, as he's logged marks of 9.00 and 2.55 in those two categories, respectively, across his prior 15 appearances for the Yankees.

As recently as May 29, Leiter was boasting a 2.28 ERA and 1.78 FIP while averaging 13.31 strikeouts per nine. Through that point in the season, he profiled as perhaps the club's second-best option out of the bullpen behind Luke Weaver while slowly entering the pantheon of high-end set-up men around the league.

Leiter's ERA has ballooned to 9.90 since then, though, which is tied for the 20th-worst total among 439 pitchers who have thrown at least five innings from May 30 through July 4.

Plenty of the responsibility for those struggles fall directly on his shoulders, but he's not the only one to blame. As noted by 'YankeesFiles' on Twitter, Statcast's Outs Above Average metric shows that New York's defense has recorded -10 Outs Above Average (OAA) with Leiter on the mound this season, representing the worst performing defense any major league pitcher has dealt with in 2025.

The Yankees, who were publicly blasted for their poor fundamentals during and after last season's World Series loss to the Los Angeles Dodgers, aren't exactly known for their slick fielding around the diamond.

The club has a few standout defenders, such as Austin Wells, DJ LeMahieu, Oswald Peraza, Cody Bellinger and Aaron Judge, though they're tied for the eighth-fewest OAA as a whole this season with -7.

Leiter's underlying metrics show that he's a lot better than his surface-level stats would suggest, evidenced by a 2.58 FIP while boasting a 4.54 ERA, and New York's defense is a major reason why that's the case.

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