Aron Baynes was ruled out of the Olympics last week and is now without an NBA team after being waived by the Toronto Raptors.

The decision comes a day after Toronto waived guard DeAndre' Bembry and forwards Rodney Hood and Paul Watson.

Baynes signed a two-year, $14.35 million ($A19.3m) deal with the Raptors as a free agent before the 2020-21 season.

He was a starter for the Raptors on opening night and played in 53 games with 31 starts last season.

Baynes averaged 6.1 points and 5.2 rebounds per game, and his shooting percentage dropped to 44.1 percent, the lowest mark since his second NBA season in 2013-14.

A key member of Australia's team at the Tokyo Games, the 34-year-old centre suffered a neck injury during the pool game against Italy and then later "slipped in the bathroom and suffered further injury".

The triple Olympian's unavailability is a big blow to the Boomers, who face the United States in a semi-final on Thursday (1415 AEST).

"I am really disappointed that I can't continue in the Olympics," Baynes said.

"I along with the rest of the team have been working so hard in our quest for an historic Olympic medal and I am gutted that I can't complete the journey with the boys', but I have every confidence that they will get the job done."

Two years removed from their 2019 NBA title, the Raptors are rebuilding.

Guard Kyle Lowry is headed to the Miami Heat in a sign-and-trade that netted Toronto guard Goran Dragic and forward Precious Achiuwa.

But the team does still have power forward Pascal Siakam and guard Fred VanVleet from their title run, and they've reportedly reached a three-year, $54 million ($A73m) deal to retain restricted free agent Gary Trent Jr.