NEW YORK — Miami Marlins left-handed reliever Andrew Nardi landed on the 15-day injured list with a left rib cage stress reaction, an injury manager Clayton McCullough said will sideline the 27-year-old well beyond the minimum 15-day stint.

“He’s been feeling this for a while,” McCullough said before the Marlins’ 6-1 loss to the Mets at Citi Field. “He was able to pitch, and when we got here, he had mentioned it was just getting harder for him to get loose. He felt worse when we got here to New York, so had the imaging done, and the IL placement was going to be necessary. He’s going to be down some time. We’ll probably get a more specific timeline tomorrow, but it’s going to be – we think – certainly more than the 15 days an IL stint requires.”

Nardi, who carries a 5.16 ERA, 1.41 WHIP, 4.4 BB/9 and 10.7 K/9 across 25 outings and 22 2/3 innings this season, said the discomfort first surfaced during the April 13-15 series in Atlanta. His last appearance came against the Blue Jays, when he surrendered a decisive solo homer in a season-high-tying 1 1/3 innings.

“That last outing in Toronto might have just pushed it over the edge,” Nardi said. “It’s been a little bit difficult breathing lately, and then even on the off-day here, I woke up and it kind of hurt to roll over a little bit, and I felt it, so just went and got it checked out.”

Nardi said the injury did not affect his velocity or stuff on the mound but made the build-up to pitching painful. “Honestly, in game, didn’t feel that at all,” he said. The IL placement is retroactive to Thursday. The setback is the latest in a string of health problems for Nardi, who missed all of 2025 with recurring back trouble and had his 2024 season cut short at 49 2/3 innings by a left elbow muscle injury. “Unfortunately I’ve been in that situation already [rehabbing], and it sucks,” Nardi said. “Definitely unfortunate right now, especially after missing all last year, but just got to keep my head up and keep going.”

Miami recalled right-hander William Kempner from Triple-A Jacksonville as the corresponding roster move. Kempner threw a perfect eighth inning on 12 pitches, maxing out at 97.5 mph. He made his Major League debut earlier this month at loanDepot park, tossing a perfect inning on eight pitches against the Orioles on May 5. In 19 games for Jacksonville, Kempner posted a 4.56 ERA, 1.21 WHIP, 16.1 K/9 rate and five saves.

“We like Will a lot,” McCullough said. “He’s kind of got the up shoot with the velocity, can spin it, and he was throwing well in Triple-A. We believe [he’s] another quality arm that certainly can provide us some depth right now, but moving forward we believe [he] can be a big part of our ‘pen.”

With Nardi sidelined, Miami’s bullpen retains two left-handed options: veteran John King, who carries a 1.93 ERA in 26 appearances, and second-year pitcher Cade Gibson, who has an 8.59 ERA in five outings. Kempner is the second rookie reliever recalled from Jacksonville this weekend, joining right-hander Josh Ekness. McCullough said the club expects a more specific timeline for Nardi’s return as early as Sunday.