Robert Williams misses first summer league practice due to missed flight

Robert Williams got the benefit of the doubt last week from most people when he missed his first conference call with the media the day after he was drafted by the Celtics. The 20-year-old won't receive that luxury again after he missed the team's first summer league practice on Sunday in Waltham.

The No. 27 overall pick returned to Texas A&M after an introductory press conference on Friday and missed his scheduled flight back to Boston, according to the team. He was in transit to Boston as of Sunday afternoon and is expected to practice with the team on Monday, but the situation will lead to plenty of more questions about the reliability of the big man as his rookie season begins.

“We expected him to be here but obviously he missed his flight," Celtics summer league head coach Jay Larranaga said. "So we’re excited for him to get here tomorrow and get started.”

Needless to say, the team was not pleased with the situation.

“I think everyone’s disappointed," Larranaga said. "You want to get everything off to a good start in the first day, but we’ll handle that internally and move forward.”

"I heard about it," Jabari Bird added. "Obviously unfortunate, but simple rookie mistake. He’ll make up for it when he gets here tomorrow."

Williams' off-court issues were a factor as the 6-foot-9 athletic center fell to No. 27 on draft night after being projected to land in the lottery. When pressed about his maturity issues, Larranaga did his best to withhold judgment.

“I’ve never met him," he said. "So I can’t really speak on anything but my personal interaction. I think with every rookie that comes into the NBA it’s really a race to maturity, and some people are further ahead like a Jayson Tatum. And a lot of guys have some work catching up to do. So Robert, like I said, when he gets here tomorrow we’ll start working with him. And I’m just excited to get to meet him.”

Other practice notes

--Tatum is not playing with the Celtics summer league team in Las Vegas but he did practice with them on Sunday.

"We’ve had Terry and Marcus last year come back," Larranaga said. "And I think that’s how you build culture. Players learn from other players. So having Jayson here, letting everyone see how he works, why he had such a successful rookie year is I think important.”

Tatum won't travel with the team to Las Vegas since he'll be helping to run a basketball camp with Kyrie Irving back near his hometown of St. Louis.