The Los Angeles Times reports that the Dodgers have tentatively slated Hyun-Jin Ryu to start Wednesday against the Diamondbacks. It was initially thought he could be ready to return from a stiff back as soon as Tuesday, but the team will call upon Edinson Volquez to take the mound for that start.
Ryu will throw a bullpen session on Sunday, and his status for Wednesday should be clearer after his session.