Robert Williams III has no limitations after knee surgery late in the regular season. Charles Krupa/Associated Press

Remarkable though it seems, from the various aches of Marcus Smart and Jaylen Brown through the return of Robert Williams, the Celtics are expected to be at full strength for Game 3 following Smart’s upgrade to probable after he missed Game 2.

And in the case of Williams, the just-completed three-day break means three more days of developing timing and losing the rust following his recovery from left knee surgery.

“Very impressed with how Rob tackled this setback,” Al Horford said following Friday’s practice. “He was the first one in here every day, working on his body, working on different things – conditioning, just doing what he could to help us. He knew how much we needed him, and I was just really impressed with his consistency.

“That speaks to him – all year he’s been consistent, weight room, treatment, getting his shots in, all the things on the court,” he said. “But all the off-the-court stuff is what’s really impressed me with him. He’s taken a huge leap just in this year, and it’s a big credit to him, the time he’s put in and the work he’s put in is showing. We’re grateful for it, because he was able to come back. We weren’t expecting him to be back in the first round, and he was able to come back and be with us. He’s obviously a huge part of what we do.”

That especially counts for Horford, who has developed quite the two-man game with Williams this season at both ends of the floor, from rim protection to an elite passing game.

From what Horford can tell, the chemistry behind this connection is back to where it was before Williams’ injury.

“I think it’s good,” said Horford. “The one thing we have to take into account is that it’s in the playoffs, and things change how teams are guarding. But him and I was are still on the same page. We’re still looking out for each other. I have his back, he has my back on the defensive end, and on offense we’re trying to make the game easy for one another. So it’s just us continuing to work, and play these games and figure things out as a group.”

SMART, WHO PREDICTED a return to the lineup while also admitting that he’s still limited by the deep bruise in his right quad, is expected to return after only missing one game. He sustained two hits on the site of an injury from earlier in the season during Game 1. Brown, fresh off his 30-point Game 2 performance, has recovered well from a nagging right hamstring injury.

“Marcus is doing much better. Went through shootaround today, walked through, got some extra work in and he will be listed as probable,” said Coach Ime Udoka. “Jaylen is good. Nothing talked about, nothing discussed. He felt fine after the game. Like I said, took him out of the game, late in the game, because of those long stretches and our lead at the time. So Jaylen’s fine.”

JUST AS UDOKA’S year on the Brooklyn staff paid a huge dividend during the Celtics’ four-game first round sweep of the Nets, Celtics assistant Ben Sullivan’s time on the Milwaukee staff is making a difference now.

“I think it is a benefit,” said Udoka. “It’s a different layer to understanding the personnel. I dealt with that obviously with Brooklyn. Anybody can scout a team, talk about their plays, their tendencies as far as that.

“Actually getting to know certain players and being around them and understanding preparation and how they respond to different things is beneficial. You saw that with me being around different guys. He’s the same way with Milwaukee. (Giannis) Antetokounmpo’s a guy he worked with for years. Any little clue as far as what they like, don’t like and any other tendencies I think goes a long way in a series. Not underrated at all. The plays and we talk about running plays, anybody can do that. Scout things out. But to know the personnel and players, more so than that, and even the coaching staff and how you go about things is very beneficial.”