"I'm pretty close; I just couldn't give you a day," Hart said. "Every day, [medical staffers] are closer to setting a day. I think they're waiting for the running stuff to get better."
For the past week or so, Hart has been a full participant in batting practice, and he has been taking ground balls at first base. But he remains limited while running, especially in the side-to-side agility drills he did Tuesday.
The knee feels good, Hart said. But his muscle memory is lagging behind.
"When I started on the field five days ago, it was terrible," Hart said. "Today was better than yesterday. Every day is progress."
Hart is eligible for reinstatement from the 60-day disabled list beginning Thursday, a target he will certainly miss.
Adam McCalvy is a reporter for MLB.com. Read his blog, Brew Beat, and follow him on Twitter at @AdamMcCalvy. This story was not subject to the approval of Major League Baseball or its clubs.