Harrison, who has worked just 10 2/3 innings this season, hasn't pitched since April 6. Later that same month, he underwent the first of two surgeries to repair a herniated disk. Here's more from Andro:
There are no problems from Harrison's back surgery. Just felt he may be trying to get back too soon. Met with Dr. Drew Dossett today.— Anthony Andro (@aandro) August 13, 2013
The 27-year-old notched standout seasons in 2011 and '12 and in January signed a five-year, $55 million contract extension that includes a team option for 2018.
Normally, this would be discouraging news, but the Rangers of course added Matt Garza to the fold before the non-waiver trade deadline, which means they're not as thin in the rotation as they once were.