McCullers (back) is expected to make a rehab start with Double-A Corpus Christi on either Wednesday or Thursday, Jake Kaplan of the Houston Chronicle reports.
The Astros will move McCullers down a rung for his next outing after he issued five free passes over three innings for Triple-A Fresno on Friday. His control had been shaky (nine walks over 14.1 innings) in the weeks leading up to his placement on the DL, but so long as he shows improvement this week, McCullers should be back contributing for the big club in short order.