New Celtics assistant coach Aaron Miles ready to work with Jayson Tatum

The Celtics would like to see Jayson Tatum, left, become more dominant in the post.John Tlumacki/Globe Staff

While working as an assistant coach with the Golden State Warriors last season, Aaron Miles could only watch Jayson Tatum from afar. His impressions were in line with those of most others around the NBA.

“Initially, it’s like, he’s a bucket,” Miles said. “To be honest, from an offensive scoring standpoint, he has everything. He has good footwork, pull-ups, mid-range, post work. He does everything.”

But the Celtics are hopeful that they can help Tatum unlock even more. And after Ime Udoka was hired as the team’s head coach last summer he thought Miles, his longtime friend and fellow Portland native, could be a perfect fit with Tatum. So he hired Miles as an assistant coach and assigned him to work with the two-time All-Star.

“With Jayson, I’m just trying to feel him out right now,” Miles said. “It’s still a new relationship. I’m trying to build a relationship and build trust, because I think that’s the most important thing. My whole thing is being genuine with people.”

Tatum’s abilities as a scorer have been well documented, but Miles said that over these first few weeks he has been struck by the forward’s skills as a playmaker, too. Now, Miles said, the Celtics are focused on helping Tatum become more dominant in the post, where he can become more of a threat to go to the foul line.

Sometimes, that will be the result of aggressive moves to the basket. But other times it will simply be a matter of awareness, such as when Tatum can draw fouls on post-up entry passes when the Celtics are in the bonus.

“It takes some time,” Miles said. “It’s not about to happen overnight, but on the court he’s already accomplished a lot in a short period of time. He’s young but he’s had some success and he’s done a great job. So I’m not coming here saying ‘You need to do it like this.’ No, I’m going to continue to observe and figure out some things, and if I see something I think can help, I’ll share it.”

Udoka drawing from Stevens

Most NBA general managers do not have head coaching experience. Not only has Celtics president of basketball operations Brad Stevens been a head coach, but he spent eight years guiding this Boston team that he now oversees.

Udoka said that Stevens has not really been involved in building game plans, but the two speak daily and Stevens has been a valuable resource.

“It’s a unique situation, but I look at it as a benefit that I have an ex-coach in the building, someone that’s worked with these guys for eight years,” Udoka said. “And we’re obviously talking through roster spots and rotations and lineups and certain personnel. That’s someone you can obviously walk right down the hall and lean on for advice on certain things and how he dealt with certain guys. So I look at that as a huge benefit to have him in the building. It’s been great so far.”

Dependable Al

Udoka said the Celtics have discussed whether to play veteran big man Al Horford in games on back-to-back nights, and that they are leaning toward giving him that chance. Horford turned 35 in June and is entering his 15th NBA season, but he was able to recharge a bit with the Thunder last season, when he played in just 28 games because the team was focused on developing its younger players.

“Al’s come in in great shape,” Udoka said. “He knows what he brings to the team and a goal of his is to obviously play in a ton of games. We’ll discuss things down the line as we get into the season, but for now, [he’ll play] … He feels great, he looks great. He’s in great shape. So that’s something he wants to do is be an every night guy, someone we depend on for leadership and things on the court.”

Horford was a mentor to fourth-year big man Robert Williams during his rookie season, and Williams said the two have picked up where they left off.

“It’s been great these last couple of weeks as far as Al just giving me a lot of teaching points,” Williams said, “a lot of stuff to look for as far as when he got the ball, just communicating with me telling me what he’s going to do. So it’s been good.”

One-sided rivalry

The Celtics have mostly controlled their duels with the 76ers in recent seasons, including an 8-1 playoff record over the last four years. Celtics guard Josh Richardson, who played for Philadelphia during the 2019-20 season, said 76ers All-Star center Joel Embiid snuffed out the idea that Boston was a true rival.

“Joel shut all that down,” Richardson said. “He was like, ‘They always kick our [butts] so it’s not a rivalry so we’re treating it like that.’ So I mean, it wasn’t really much of a rivalry, it was just like, ‘These guys are good, and are coming in here to whoop us, so let’s compete.’”

Adam Himmelsbach can be reached at [e-mail]. Follow him on Twitter @adamhimmelsbach