Turnbull is slated to start Tuesday against the Phillies after the Tigers placed Tyson Ross on the paternity list.
Turnbull had been ahead of Ross in the Tigers' pitching order last week, but the team elected to swap the two for the two-game set in Philadelphia, likely due to the impending birth of the latter's child. The change was for naught after Ross ultimately needed to leave the team earlier than anticipated, so Turnbull now tentatively lines up for a two-start week, assuming the Tigers wait until next week to add a fifth rotation member to the mix to replace the injured Jordan Zimmermann (elbow). Turnbull's second turn is set to come Sunday against the Royals in Detroit.