Turnbull will start Game 2 of Tuesday's doubleheader against the Red Sox, Anthony Fenech of the Detroit Free Press reports.
Turnbull will follow Matthew Boyd, who is scheduled to start the first game of Tuesday's twin bill. Through four starts this season, the 26-year-old right-hander owns a 3.43 ERA, 1.29 WHIP and 10.3 K/9 across 21 innings.