The Red Sox placed Gray on the 15-day injured list Tuesday with a right hamstring strain.
The veteran right-hander departed Monday's start against the Tigers after 2.2 frames due to hamstring soreness, and he's been diagnosed with a strain after undergoing medical imaging. Gray will be eligible to be reinstated from the IL in early May and is hopeful it won't be a lengthy stay on the shelf, per Chris Cotillo of MassLive.com, but he's without an official timeline for return. Top prospect Payton Tolle had his start for Triple-A Worcester skipped over the weekend as a contingency plan, and he could soon be promoted to take Gray's rotation spot.