BOSTON — Boston Celtics first-round draft choice Robert Williams got a lecture from the team about accountability and said they are moving on from the bad first impression he made by missing a flight and failing to get back in time for summer league practice.

“It’s all on me,” Williams told reporters Tuesday, a day after he missed practice. “So we’re going to push forward and move past that.”

A potential lottery pick who dropped to the Celtics at No. 27 because of questions about his work ethic, the forward out of Texas A&M overslept for a conference call with reporters the morning after the draft, blaming the difference in time zones. He was in Boston last week for an introductory news conference, where he said he knew he would have to work hard to make it in the NBA.

Then he went home to Louisiana and missed his flight back.

Williams, 20, said he was upset with himself for making a bad first impression.

“Missing my flight didn’t help,” he said. “I talked to Coach (Brad) Stevens when I got back and he obviously explained to me about the opportunity. There’s not that many. So, definitely a real wake-up call.”

NUGGETS: Denver agreed to a multiyear deal with rookie forward Michael Porter Jr., who was taken with the 14th overall pick in the draft last month.

MAGIC: Mo Bamba, the No. 6 pick in the draft, signed his rookie deal.

CLIPPERS: Avery Bradley is staying with Los Angeles, agreeing to a two-year contract.

Yahoo Sports said the contract will be worth $25 million.

Bradley played in 46 games last season between the Pistons and Clippers.

Bradley was traded to the Clippers in January as part of the Blake Griffin deal, then made only six appearances with Los Angeles before being shut down with a hernia.

n Mike Scott, an unrestricted free-agent forward, agreed to a one-year deal. Scott played last season with the Wizards.

JAZZ: Utah has kept two of its internal targets, signing Raul Neto and Dante Exum. Exum agreed to a three-year extension that will be worth around $33 million and Neto agreed to a two-year contract extension.

PACERS: Tyreke Evans had plenty of suitors, and decided to sign with Indiana.

Evans has agreed to a one-year deal that will be worth $12 million for next season.

WIZARDS: Jeff Green is heading back to Washington, the city where he played college basketball at Georgetown.

Green agreed to a one-year contract for the veteran’s minimum of $2.4 million.

Washington needed to add some big men after trading starting center Marcin Gortat and losing backup power forward Mike Scott to free agency.

ROCKETS: Michael Carter-Williams agreed to a one-year deal with Houston Rockets to add some backcourt depth behind MVP James Harden and Chris Paul.

Houston is Carter-Williams’ fifth team in six seasons.

WARRIORS: Versatile big man Kevon Looney will re-sign with Golden State.

Bringing back Looney, a power forward and center, was a top priority for GM Bob Myers to keep the young core of the two-time defending NBA champions together.