What to Know About Dolphins DT Zach Sieler's Mysterious Season-Ending Injury

The Miami Dolphins will be without their best defensive lineman for the rest of the 2026 season

Miami Dolphins defensive lineman Zach Sieler (92) walks off the field after the game against the Detroit Lions at Hard Rock Stadium. | IMAGN IMAGES via Reuters Connect

There indeed was a major announcement regarding Miami Dolphins defensive tackle Zach Sieler on the day of the NFL trade deadline, but it had nothing to do with him being moved.

Instead, the bombshell report involved a season-ending injury for the team captain.

Sieler ruptured a biceps tendon against the Detroit Lions on Sunday and will undergo season-ending surgery, according to ESPN insider Adam Schefter, citing sources.

Dolphins standout DT Zach Sieler ruptured his biceps and will undergo season-ending surgery, with a 5-6 month recovery expected, per sources. The injury happened on first play Sunday and he played the whole game with it. pic.twitter.com/N1ys0kzlkD

— Adam Schefter (@AdamSchefter) November 10, 2026

The longest-tenured member of the roster, Sieler had been remarkably durable since joining the Dolphins as a waiver pick-up from the Baltimore Ravens in 2019, missing only two games over the past six seasons — that came in the 2024 season when he was poked in the eye during practice.

STRANGE SERIES OF EVENTS

To say this news came out of nowhere would be putting it mildly, considering Sieler played 42 snaps in the 19-9 loss against the Lions, only four fewer than he played against New England in Week 8.

There also was no Sieler injury reported in the press box, with the only one reported by the Dolphins being the quad injury to Will Kacmarek after he took a shot after catching a pass near the sideline.

No injury being reported could be explained by Sieler not being tended to on the field or being away from the sideline at any point.

What is notable, however, is that on the very first play from scrimmage against Detroit, a 2-yard run by Jahmyr Gibbs, Sieler was sporting a black contraption around his right upper arm. Sieler was listed on the injury report last week with a shoulder injury and was a limited participant in practice Wednesday and Thursday before being full go Friday.

Against the Lions, Sieler finished with one tackle, good for a 3-yard loss on a running play by Gibbs. While he didn't register a stat on the play, it was his initial pressure on Jared Goff that forced the quarterback out of the pocket and led to the third-down sack by Josh Uche in the first half.

SIELER STAYING PUT

The injury obviously quashed any notion of Sieler being traded before the 4 p.m. ET deadline Tuesday, even though reports indicated earlier the Dolphins had no intention of moving on from him regardless.

Sieler has three more years left on the contract extension he signed in September 2025. He's got a cap number of $20.8 million next year with no guaranteed salary remaining, which would seem to make him a potential candidate for a contract restructure.

That's down the line, though.

The immediate impact is the Dolphins will be left without their best defensive lineman.