The Orioles' second baseman was not given a timetable for his return, and he is still not allowed to resume full baseball activities.
The sign of improvement is some of the only positive news Roberts has received since sustaining the injury while sliding headfirst into first base on May 16 at Fenway Park. He was cleared to begin a plan of light upper-body exercise by Collins on June 21.
This is the second time in as many seasons that Roberts has been bothered with a long-term injury; he missed 59 games in 2010 with a herniated disk in his lower back. The 33-year-old infielder also battled back and neck injuries this Spring Training after another headfirst slide into first base.