Ray is listed as the Padres' probable pitcher for Friday's game against the Astros in Houston.
Ray will be taking the hill on seven days' rest as he makes his debut for the Padres, who acquired him Monday in a deal that sent right-hander Miguel Mendez and shortstop Joniel Hernandez to the Giants. The 34-year-old southpaw was one of two additions to the rotation at the deadline, as the Padres also brought aboard Casey Mize from the Tigers. Ray will look to aid the Friars' playoff push over the next seven and a half weeks before heading into free agency this winter.