Veteran centre JaVale McGee and Spurs guard Keldon Johnson look set to be added to the 12-man Olympics roster.

It means much of the USA roster will have little time together before its Olympic opener on July 25 against France.

Johnson, who plays for USA coach Gregg Popovich in San Antonio, is a member of the select team of young players training against the Americans.

McGee, who played for the Cleveland Cavaliers and Denver Nuggets last season, has won three NBA titles but has no Olympic experience.

Love's agent, Jeff Schwartz, confirmed the Cleveland Cavalier forward's withdrawal on Friday.

"I am incredibly disappointed to not be heading to Tokyo with Team USA, but you need to be at absolute peak performance to compete at the Olympic level and I am just not there yet," Love said in a statement.

Love's withdrawal comes a day after the Americans announced that Washington Wizards guard Bradley Beal would miss the Olympics because he was in health and safety protocols.

Love would have been trying for a second Olympic gold medal, having played for the Americans in London in 2012.

He also was on the team that won gold two years earlier in the world championships.

That past USA Basketball experience helped him get selected for this roster despite his difficult NBA season.

Love missed 46 games because of the injury and averaged just 12.2 points in 25 games.

He played in two of the Americans' three exhibition games in Las Vegas, scoring one point.

The USA was already short-handed before the losses of Beal and Love. Milwaukee's Jrue Holiday and Khris Middleton, along with Phoenix star Devin Booker, won't join the team until after the NBA Finals.

The Americans cancelled their exhibition against Australia scheduled for Friday night because of health and safety concerns.

Australian Associated Press