Doc Rivers said Garnett participated in a little more than half the practice, going through plays and running up and down the court, but the coach ruled his star forward out for Friday's home game against Charlotte.
"He went through half the practice or more than that, actually," Rivers said. "He looked pretty good. He's not playing [Friday] but he looked pretty good. Besides just his wind, I thought his movement was very good. I want to see him another practice but he's getting close."
Rivers said trainer Ed Lacerte and team doctor Brian McKeon checked out Garnett and cleared him to participate in all the contact drills and plays in practice.
"There were a couple of times I wanted him off the floor and he stayed on the floor and did all the pick-and-roll defense live," said Rivers. "We went up and down and he did all that live."
Boston is 5-3 without Garnett in the lineup.
The Celtics received more discouraging news as two more frontcourt players are dealing with injuries that could keep them sidelined indefinitely. Jermaine O'Neal had an MRI Thursday on his sore left knee that acted up in the second half of Monday's game against Houston, and backup center Semih Erden missed practice because of a groin pull.
Rivers is concerned that O'Neal will likely need surgery.
"Don't know yet," Rivers said. "Honestly, my guess is they're going to have to do something. So, I don't know that. I'm just using my doctorate right now. My guess is they'll probably have to do something."
Boston's depth in the frontcourt was already slim with Kendrick Perkins (right knee) not yet cleared to practice and Shaquille O'Neal getting limited minutes to maintain his stamina for later in the season.
"It puts more pressure on them," Rivers said of his healthy big men. "This is who we are right now. It's part of it."