The Cubs are placing starting pitcher Jameson Taillon on the 15-day injured list with a strained right calf. The team revealed the news to reporters (including Patrick Mooney of The Athletic) this morning and confirmed the transaction shortly thereafter. Jordan Wicks is coming up from the Triple-A Iowa Cubs to take Taillon’s spot on the active roster. However, manager Craig Counsell said that Chris Flexen, not Wicks, is the most likely candidate to temporarily join the rotation (per Bruce Levine of 670 The Score). Flexen has been working as a long reliever this season, but he made 30 starts for the White Sox just last year.
Taillon, 33, suffered the injury while running in a training session and is expected to miss more than a month (per Vinnie Duber of the Chicago Sun-Times). While he hasn’t been as effective for Chicago as he was last year, there is no doubt the Cubs will miss his reliable presence on the mound every five days. His 95 1/3 innings rank 20th among NL starting pitchers, while his 4.44 ERA (85 ERA+) and 4.24 xERA (32nd percentile) suggest he has been more than serviceable as an inning-eating back-end starter. He hasn’t looked his best recently, with a 10.66 ERA over 12 2/3 innings in his last three starts, so if there is any silver lining to this injury, it is that he will have some time to rest and reset. The Cubs will hope he returns looking more like the guy who pitched to a 3.48 ERA over his first 14 starts.
Wicks, the Cubs’ first-round pick in 2021, has never quite looked comfortable at the MLB level, with a career 5.23 ERA and 4.68 SIERA over 82 2/3 innings from 2023-25. With that said, he has looked sharp over his last handful of outings at Triple-A (16 1/3 IP, 3 ER, 20 K, 3 BB). The 25-year-old will presumably take over Flexen’s low-leverage long-relief gig. Flexen, meanwhile, shouldn’t have too much trouble transitioning back to the rotation. He started five games at Triple-A in April before he was called up to the big league club, pitching to a 3-0 record with a 1.16 ERA and 2.89 FIP. While he has not started in the majors since 2024, he tossed four scoreless innings of relief against the Astros last week, so stretching out shouldn’t be too difficult. Although Flexen was not very effective as a starter in either of the last two seasons, he has more than earned another opportunity with his excellent performance so far in 2025. In 29 innings spread out over 16 appearances, he has given up just two earned runs on 16 hits.
The Cubs have been without Javier Assad (oblique injury) all season, and Justin Steele required season-ending elbow surgery after just four starts. Shota Imanaga also missed significant time earlier this year, but the Cubs were grateful to see him back on the mound last week. Imanaga and the surprisingly dominant Matthew Boyd give Chicago a strong one-two punch atop the rotation, but the back end could be a weak spot until Taillon returns.