CELTICS NOTEBOOK: Kyrie Irving on target on opening day of training camp

The guard, who missed the end of the 2017-18 season because of a knee ailment, hit a game-winning 3-pointer to finish a scrimmage on Tuesday.

BOSTON – The end of a long first day of Celtics’ training camp was approaching early Tuesday night.

The team had gone through one practice session in the morning, then returned to the Auerbach Center later in the day for another workout that featured a scrimmage.

Starters Kyrie Irving, Gordon Hayward, Al Horford, Jayson Tatum and Jaylen Brown were trailing the reserves – Marcus Morris, Terry Rozier, Marcus Smart, Aron Baynes and Semi Ojeleye – by a point with time running out.

That’s when Irving, aided by a screen from Horford, calmly stepped up and connected on a 3-pointer with a couple of seconds to go to give the starters a win.

After missing the final month of the regular season and the entire playoff run last season because of two knee surgeries, Irving was on target in his return.

“Kyrie looked good,’’ Hayward said. “I think he’s working through some similar things that I’m working through as far as being hurt and trying to find a rhythm and a groove. But Kyrie looked like Kyrie. He’s really good.’’

Irving played his final game on March 11, then had a tension wire removed from his left knee. When an infection was discovered, another operation was needed, ending his first season with the Celtics.

He has been eager to start playing again and in the brief portion of practice that was open to the media, was having no problems moving on the court.

“Good to get started,’’ Irving said. “It felt good. I missed it, missed being with the guys. It was great to get started. It was high-level basketball.

“It felt good to finally be competing with one another and realizing we have a lot of talent on the floor. I’d rather be too deep of a team than not having enough because I’ve been on a few teams where we didn’t have enough talent.

“Guys are just so talented. We’re going to have to figure out being ourselves and playing the game the right way.’’

Irving is hoping to play in the preseason opener Friday night against the Charlotte Hornets, a game that will be played on the campus of his college rival, the University of North Carolina.

“I can’t wait to play,’’ said the Duke product. “I think we’re playing at UNC in Chapel Hill, right?. Ahhhhh. No disrespect to UNC. I can’t wait to get back to North Carolina and go eight miles down the road (to Duke).’’

Theis returns: Daniel Theis, who suffered a season-ending knee injury on March 11 after making an impact in the rotation during his rookie year, was able to participate in the first two practices of camp.

“I thought Theis looked really good,’’ said coach Brad Stevens. “He had a couple of shots that were short, almost he was surprised to take them. But I think that’s pretty normal when you come back from having sat so long. Moving wise, laterally up and down, jumping off two feet, really good.’’

Rookie Robert Williams, who missed time during the Vegas Summer League due to a left knee injury, did not take part in the scrimmage.

“We’re taking it easy on his first day of NBA practice,’’ Stevens said. “He did a ton this morning. We did 25 minutes worth of up and down this morning. He’ll be ready to play this weekend. We’re just taking it easy on the two-a-days.’’

Roster additions: The Celtics added three rookies to the roster for training camp, giving them 19 players. There are 14 contract players in camp, plus two on two-way deals (Walt Lemon Jr. and P.J. Dozier).

The three rookies taking part in training camp are Justin Bibbs of Virginia Tech, Nick King of Middle Tennessee State and Jeff Roberson of Vanderbilt.

Jabari Bird, who signed a two-year contract with the Celtics this summer, is not in camp after being arrested in a domestic assault case this month.

Jim Fenton may be reached at jfenton@enterprisenews.com. Follow him on Twitter at @JFenton_ent.