The Mariners non-tendered Thornton on Friday, Daniel Kramer of MLB.com reports.

EDGE Analysis

Thornton's 2025 season came to an abrupt halt in late July after he tore a left Achilles tendon. Prior to the injury, Thornton posted five holds along with a 4.68 ERA, 1.30 WHIP and 32:14 K:BB across 42.1 innings while operating out of the bullpen. Thornton's expected timeline to recover was estimated as 6-to-8 months after undergoing surgery in August, which will impact his availability for spring training should he sign with a team.

The Mariners transferred Thornton (Achilles) from the 15-day injured list to the 60-day injured list Tuesday.

EDGE Analysis

The transaction frees up a spot on the 40-man roster for the addition of Sauryn Lao. Thornton is out for the season after tearing his left Achilles on July 31.

Thornton underwent season-ending surgery Monday to repair a torn left Achilles tendon and is expected to face a recovery timeline of 6-to-8 months, Daniel Kramer of MLB.com reports.

EDGE Analysis

Thornton suffered the Achilles injury during a July 30 relief appearance and finished the 2025 season with a 4.68 ERA, 1.30 WHIP and 32:14 K:BB over 42.1 innings. Given the timeline laid out by Seattle, Thornton's availability for the start of spring training will likely be affected, and the injury could prompt the Mariners to non-tender him this winter as he heads into his final season of arbitration in 2026.

The Mariners placed Thornton on the 15-day injured list Friday with a torn left Achilles.

EDGE Analysis

Thornton left Thursday's game against the Rangers on a cart, and imaging confirmed Friday that the right-hander tore his Achilles tendon. The diagnosis will put an early end to his season, and he'll finish 2025 with a 4.68 ERA and 1.30 WHIP alongside a 32:14 K:BB through 42.1 innings. The 31-year-old will likely miss the vast majority of the 2026 season as well.

Thornton (leg) was on crutches following Thursday's game against the Rangers, and he believed he suffered a serious Achilles injury, Daniel Kramer of MLB.com reports.

EDGE Analysis

Thornton was injured while trying to cover first base late in Thursday's game and appeared to suffer a serious leg injury. He is set for an MRI on Friday, at which time a diagnosis should become official.

Thornton suffered a left leg injury Thursday against the Rangers and departed on a cart, Adam Jude of The Seattle Times reports.

EDGE Analysis

Thornton entered the game in the eighth inning and successfully recorded five outs. He then suffered what appeared to be a serious leg injury while trying to cover first base. Thornton will almost certainly need a stint on the injured list, but the issue could prove to keep him sidelined for additional time.

Thornton threw a clean seventh inning in Saturday's 7-6 extra-innings win over the Astros. He struck out one.

EDGE Analysis

Although he has just five holds this season, Thornton is beginning to settle in following a dreadful start to the year that saw him hold a 7.71 ERA as of June 10. The right-hander has worked multiple innings for the Mariners in five of his last 11 outings, during which sports a 1.06 ERA, 0.82 WHIP and 14:7 K:BB covering 17 frames.

Thornton threw 2.1 scoreless innings of relief before exiting Saturday's eventual 10-7 loss to the Cubs due to heat exhaustion per Daniel Kramer of MLB.com. He allowed one hit and two walks while fanning three.

EDGE Analysis

Thornton had to be helped off the field in the eighth inning, but he's not expected to require additional medical treatment away from the team. After throwing a season-high 51 pitches Saturday, Thornton figures to get a few days off before he's available out of Seattle's bullpen again anyway. The 31-year-old right-hander missed about a month of action due to appendicitis earlier this year, and he's mostly struggled with a 6.35 ERA, 1.50 WHIP and 17:10 K:BB over 22.2 innings.

The Mariners reinstated Thornton (abdomen) from the 15-day injured list Saturday.

EDGE Analysis

Thornton landed on the 15-day injured list May 9 due to appendicitis, and it took three weeks for him to recover enough to embark on a rehab assignment with Triple-A Tacoma. He'll claim the spot in the Mariners' bullpen that was vacated by Casey Lawrence, who was designated for assignment in a corresponding move. Thornton posted a 5.87 ERA, 1.30 WHIP, five holds and an 11:4 K:BB across 15.1 innings prior to his stint on the IL.

Thornton (abdomen) started a minor-league rehab assignment with Triple-A Tacoma on Friday, MLB.com reports.

EDGE Analysis

Thornton, who is recovering from appendicitis, tossed 16 pitches and fanned two in a scoreless inning Friday. The 31-year-old veteran right-hander has been on the injured list since May 9, but he's now tracking toward a return to Seattle's bullpen sometime around the first or second week of June. Thornton has a 5.87 ERA, 1.30 WHIP and 11:4 K:BB over 15.1 innings this season, and he'll likely work as a middle reliever once he rejoins the Mariners.