Fister, whose left-side strain has held him out since May 28, said he felt good after a bullpen session Wednesday.
"It's another step in the right direction," Fister said. "It's something I've obviously been working on for a little while. It's high anticipation to get out there and get going."
Manager Jim Leyland said the Tigers haven't decided who they'll send down when Fister comes off the disabled list, but he's excited that his starter seems to be over the hump.
The news is more grim for left fielder Andy Dirks, who is still feeling pain in his Achilles tendon when making cuts. Leyland said he knows something's not right, because Dirks is one of the toughest players on the roster.
"Something's not right," Leyland said. "We're going to double-check when we're home, [that's] kind of the plan, just to see if we're missing something.
"He doesn't appear to be real close. He gave me an indication that it's not too good. I think we're going to take a look at that a little further when we get home."