The Red Sox placed Whitlock on the 15-day injured list Thursday with left knee inflammation, Gabrielle Starr of the Boston Herald reports.
Whitlock had been unavailable to pitch the last few days after hurting his knee on a wet mound during his last appearance Sunday versus the Twins. The Red Sox wanted to give him time to improve in hopes that he could avoid the injured list, but ultimately a roster move was required. Tyler Samaniego is absorbing Whitlock's spot on the roster and in the bullpen.