McCullers (shoulder) is likely to pitch a simulated game this weekend in Buffalo, Danielle Lerner of the Houston Chronicle reports.
McCullers was placed on the injured list May 23, and the Astros are not giving a timetable for his return to the rotation. Houston's rotation was given a boost recently with Framber Valdez and Jake Odorizzi returning from injuries, but the team will make room for McCullers whenever he's ready.