UPDATE: After Friday’s shootaround, Celtics  coach Doc Rivers  said that Jeff Green  was meeting with more doctors with team president Danny Ainge. Rivers said they hoped to have resolution on Green’s status later on Friday.
Forward Jeff Green was once again a spectator as the Celtics ran through practice on Thursday at TD Garden. Green was in shorts and workout gear getting up shots, but he is still not cleared to practice due to an issue with his physical. On Tuesday, Green said that it was related to a stress test, but there has been little clarity regarding the exact nature of the situation.
“We’ll know more about Jeff [on Friday],” team president Danny Ainge said. “He’s completing all tests and results and we should know more [Friday] afternoon. Everything. We’ll wait until then to give you guys all that information.”
Ainge said they had the results of further tests, but when asked whether they were good or bad, he said, “It’s all based on perspective.”
Coach Doc Rivers also said that Paul Pierce  won’t play in Sunday’s exhibition game against Toronto because of his sore right heel. It’s too early to tell whether Rajon Rondo  (sprained ankle) will play on Sunday, but Rivers hasn’t ruled it out yet.
“Paul will be out until probably around Monday,” Rivers said. [Trainer] Eddie [Lacerte] said he could possibly play but why take the chance going from no practice to playing in an exhibition game? We’re probably going to leave him back.”
Rivers added that Sasha Pavlovic  took a hard fall in Wednesday’s practice but looked ready to participate in Thursday’s session.
PRAISE FOR GREG STIEMSMA 
One player who has stood out so far is center Greg Stiemsma. The former Wisconsin product has put in time overseas and the in the D-League where he stood out as a rugged defender and shot-blocker. (Here’s video of Stiemsma rejecting Blake Griffin  twice in summer league two years ago).
“I do like Stiemsma,” Rivers said. “I do like him a lot. He hasn’t separated himself or anything. But I like some of the things he can do. I think we have to convince what he can do. He’s actually a terrific shooter from the elbows. He’s not a post player at all. He’s a terrific shot blocker. He blocks everything.”
The Celtics have 14 players under contract (including Green), leaving one roster spot open. If they elect to keep another big man, Stiemsma is definitely on their radar.
Ainge said they’re might be another move, but their options are limited. They used their taxpayer exception to sign Chris Wilcox  and he can’t trade any of the new additions or draft picks.
“I don’t know if there’s anything I need to do, but there’s some things that we’re still working on,” Ainge said. “I think this roster is what it’s going to be. Things that we would like to do are usually difficult to pull off.”
AVERY AS AN ELITE DEFENDER
Ainge offered praise for Avery Bradley , saying that in time he could become an elite defender.
“Avery is our best athletic perimeter defender,” Ainge said. “He’s young, without experience, so he has to learn to use that athleticism. He’s also a very intense kid. He’s athletic strong and intense and has a ton of energy. Once he learns to bridle that energy he can be one of the best defenders in the league.”
The Celtics acquired Keyon Dooling  in part because he will serve as Rondo’s backup. That, in turn, lessens the pressure on Bradley to run the offense, which he clearly struggled doing last season. (Here’s more on how that dynamic works ).