Gallen (hamstring) is expected to be activated off the injured list and start Saturday against the Cubs, Nick Piecoro of the Arizona Republic reports.
Gallen made a quick recovery after tweaking his right hamstring July 2. This will be his second return from the injured list this season, and the right-hander is hopeful this one lasts longer than the first. He had spent time on the IL with an elbow injury and appeared in four games before going down with the hamstring issue.