Duffy (hamstring) ran at 85 percent Friday, Marc Topkin of the Tampa Bay Times reports.
Duffy said his hamstring felt "okay" and he was still a little sore Saturday, so he still has a few hurdles to cross before he is ready to play for the Rays again. There is currently no timetable for Duffy's return, but he is hoping to be back on the field at some point this season.