Updated

HOUSTON (AP) -- The Houston Astros have placed right-hander Lance McCullers on the 10-day disabled list with a back problem, another blow to a rotation decimated by injuries.

His stint on the DL with discomfort in his lower back is retroactive to June 9. General manager Jeff Luhnow says the team doesn't expect it to lead to a "long absence" for McCullers but didn't specify a specific timetable for his return.

McCullers joins ace Dallas Keuchel and right-hander Charlie Morton on the 10-day disabled list. Houston has also been without starter Collin McHugh, who is on the 60-day disabled list, all season.

McCullers is 6-1 with a 2.58 ERA in 13 starts this season.

There was some good news for the first-place Astros on Monday with right-hander Joe Musgrove coming off the disabled list to start against the Rangers.