As soon as the Boston Red Sox appear to have a good thing on their hands, this season has shown a tendency to snatch that thing away.
The Red Sox's bullpen was beginning to form a bit of an identity during their occasional May winning streaks. When righty Justin Slaten came off the injured list, Boston had a trio of relievers that could seemingly get them through the seventh, eighth, and ninth innings reliably. Unfortunately, that formula unraveled when Slaten and Garrett Whitlock had some recent rough outings, and then the news got far worse.
On Thursday, prior to the series finale against the Atlanta Braves, the Red Sox placed Whitlock on the 15-day injured list with left knee inflammation. He was replaced on the active roster by left-hander Tyler Samaniego, who was previously optioned to Triple-A Worcester on Sunday.
The #RedSox today placed RHP Garrett Whitlock on the 15-Day Injured List (retroactive to May 25) with left knee inflammation. To fill his spot, Boston recalled LHP Tyler Samaniego from Triple-A Worcester.
— Red Sox (@RedSox) May 28, 2026
Whitlock's season was off to a tremendous start, even after his rough outing on Sunday spiked his ERA from 2.79 to 3.20. There's really no replacing him as one of the most prolific setup men in the sport, especially as he's proven to be almost equally dominant against right-handed and left-handed batters.
Samaniego has a 1.04 ERA on the year, but it's definitely a bit of a smoke-and-mirrors situation. His FIP sat at 3.88 entering Thursday, and he also doesn't have nearly the same pedigree Whitlock has in high-leverage situations.
While a knee injury for a pitcher isn't necessarily as concerning as an arm injury, the Red Sox could ill afford to lose one of their best run preventers as they try to climb back from eight games under .500. All that can be done is to hope that Whitlock recovers quickly, and that relievers like Slaten, Samaniego, and Greg Weissert can hold down the fort to some degree.