Australian point guard Patty Mills says the gorilla is off his back after edging out two NBA veterans to secure the 15th and final spot on the Portland roster for the upcoming NBA season.

Mills was initially signed by the Trailblazers last weekend to a one-year non-guaranteed contract for the rookie minimum wage.

But the Australian could still have been waived by the franchise prior to the start of the season on October 27.

However, despite being currently sidelined with a broken foot, the Trailblazers' coaching staff gave him the nod ahead of veterans Ime Udoka and Jarron Collins.

The two-year deal is expected to be worth just under $US1 million ($A1.08 million).

Mills will be one of four Australians playing in the NBA this season alongside Milwaukee's Andrew Bogut, Minnesota's Nathan Jawai and Houston's David Andersen.

"This is amazing, it's such a good feeling," said Mills.

"It feels like I finally got the gorilla off my back.

"It was a massive gorilla and there were times when I thought I wasn't going to make it, but finally I've got rid of it and now I just want to be part of the team."

Once he recovers from the broken foot, Mills will probably spend time in the NBA's Development League with Portland's feeder club Idaho Stampede to build up match fitness.

Mills impressed NBA scouts with two standout performances for the Boomers against the United States last year.

He scored an equal team-high 13 points in a pre-Olympic exhibition game in Shanghai and then top-scored with 20 points in a match at the Beijing Games.

Trailblazers head coach Nate McMillan is an assistant coach with Team USA and saw both performances first-hand from courtside.

Portland selected Mills with the 55th overall pick in the second round of the NBA draft in April after playing two seasons at St Mary's College in California.

The NBA regular season opens on October 28 (AEDT).