Seattle placed Hancock (groin) on the 15-day injured list Sunday with a left adductor strain, retroactive to Aug. 29.
Hancock felt something off in his left leg early on in his most recent start Friday against Toronto. The 27-year-old went on to take the loss after allowing five runs over five innings. The right-hander will miss a minimum of 15 days and a couple of starts for Seattle. The Mariners recalled Nick Davila from Triple-A Tacoma to fill in for Hancock on the 26-man roster.