Red Sox lose setup man Tyron Guerrero to IL

What a find Guerrero has been for Boston. In his first MLB action since 2019, he has a 2.45 ERA and a 23/2 K/BB in 18 1/3 innings since being called up in late May. The walk rate is simply astounding. Guerrero has always had a great arm, but he couldn’t establish himself in the majors previously because of control issues. He improved there during his time in Japan, but even so, he still walked nine percent of the batters he faced for Chiba Lotte last year. Right now, he’s at three percent. Guerrero is 35, but if he keeps throwing strikes, he could well help the Red Sox beyond 2026.

What a great story and moment for Guerrero. The 35-year-old has not pitched in an MLB game since 2019 as a member of the Miami Marlins. After that, he missed a season during the COVID year, played in the minors in the White Sox organization, went to Japan, got another chance in the Reds organization, went to play in Mexico, got a chance in the Angels organization, went back to Japan, and then got a minor league deal with the Red Sox this winter. In 19 2/3 innings at Triple-A this season, Guerrero has a 0.92 ERA, 0.97 WHIP, and a 22/6 K/BB ratio while touching triple digits on the radar gun.

No word yet on the corresponding move(s) that the Red Sox will make to the roster. Guerrero, 35, holds a scintillating 0.92 ERA, 0.97 WHIP and a 22/6 K/BB ratio across 19 2/3 innings in 15 appearances at Triple-A Worcester this season. He’ll bolster the club’s middle relief corps.

Capra was in Red Sox camp as a non-roster invitee and failed to land a spot on the club’s season-opening roster in a bench role. Delay is merely emergency catching depth while Guerrero and Keller could be up as stopgap relief options at some point later this year.

The 35-year-old hurler hasn’t pitched in the big leagues since the 2019 season. He spent the 2025 campaign toeing the slab for the Chiba Lotte Marines of Japan’s Nippon Professional Baseball where he registered a 3.60 ERA, 1.32 WHIP and a 46/23 K/BB K/BB ratio across 50 frames. He’ll add bullpen depth for the Red Sox.

The deal will pay the 6-foot-8 right-hander $600,000. Guerrero will head overseas after spending 2024 in the Angels’ organization. The 33-year-old could be back with an MLB club with a strong showing overseas, but he hasn’t pitched in the majors in five years.

Guerrero was pitching in relief in the Rays system in 2023 but was released in June after posting an 11.51 ERA, 2.25 WHIP and 20/22 K/BB ratio across 22 2/3 innings (20 appearances) for Triple-A Louisville. He then headed to the Mexican Winter League with the Naranjeros of Hermosillo, where he pitched to a 1.10 ERA in16 1/3 innings with 26 strikeouts and also he has the fastest pitch of the season at 101.6 MPH. He will look to impress his new organization in the spring but seems most likely to operate as bullpen depth.

Guerrero signed a minor league contract back in March and winds up heading back to the free agent waters after posting an inflated 11.51 ERA, 2.25 WHIP and 20/22 K/BB ratio across 22 2/3 innings (20 appearances) for Triple-A Louisville. The 32-year-old righty hasn’t appeared in the majors since the 2019 campaign.

The latest batch of cuts trims the Reds’ camp roster to just 45 players. Guerrero, Herget and Duarte represent organizational relief depth, while Martin is also likely to stick around at Triple-A Louisville as extra depth.

Guerrero last pitched in the majors for the Marlins during the 2019 campaign. The towering 6-foot-8 righty features triple-digit fastball velocity and spent last year with the Chiba Lotte Marines of Japan’s Nippon Professional Baseball, posting a 3.52 ERA, 1.17 WHIP and 63/20 K/BB ratio across 46 innings (49 appearances). He’ll compete this spring for a spot on Cincinnati’s Opening Day roster.