Australia’s Duop Reath, right, fouls United States’ Bam Adebayo during an exhibition basketball game Monday at Las Vegas. John Locher/Associated Press

LAS VEGAS — These games don’t count. Right now, that is the only saving grace for USA Basketball.

And for quite probably the first time in 29 years of NBA players suiting up for the national team, they heard boos when a game ended – on home soil, no less.

Patty Mills scored 22 points and Australia held the U.S. without a field goal for the final 4:34 on the way to beating the Americans 91-83 on Monday night, dropping the three-time defending Olympic gold medalists to 0-2 in their five-game slate of exhibitions leading up to the Tokyo Games.

Joe Ingles scored 17 points, Matisse Thybulle scored 12 and Chris Goulding had 11 for Australia.

Damian Lillard led the U.S. with 22 points, and Kevin Durant scored 17 and Bradley Beal finished with 12. But the Americans wasted a 10-point second-half lead, and have dropped back-to-back games for just the third time since NBA players began wearing the red, white and blue in 1992.

The other instances: two straight in the 2002 FIBA World Championship and two straight in the 2019 Basketball World Cup. The U.S. finished sixth in the first tournament, seventh in the other. And while these are glorified scrimmages, this much is already certain – a medal seems far from a lock for the U.S.

Jayson Tatum’s layup with 4:35 left put the Americans up 82-80. Australia outscored the U.S. 11-1 the rest of the way, and Mills – who plays for U.S. Coach Gregg Popovich in San Antonio – did most of the damage down the stretch.

Favored by 16.5 points before the game, according to FanDuel Sportsbook, the Americans looked the part for much of the first half. A 20-6 run – capped by five points from Select Team call-up Keldon Johnson – put the U.S. up by eight late in the opening quarter, and Lillard closed out his 16-point first half with a 3-pointer 31.7 seconds before intermission that gave the Americans a 46-35 lead.

The halftime lead was nine, the same lead that the U.S. had early in the third quarter against Nigeria before letting it slip away.

And the same thing happened in this one.

The third-quarter lead for the U.S. was as big as 10 and was 58-50 when Lillard made a 3-pointer midway through the quarter. But Australia closed the quarter on a 19-6 run, Goulding hit a 3-pointer as time expired and Australia took a 69-64 lead into the final 10 minutes.

NOTES: The Americans changed the starting lineup, with Jerami Grant in for Jayson Tatum and Draymond Green in for Bam Adebayo. … The U.S. was outrebounded 32-25. … Kevin Love, who played only three minutes in Saturday’s loss to Nigeria, was the only Olympic-teamer who didn’t get into the game for the U.S. The Americans used 10 players; the eight other Olympians in Las Vegas, plus Select Team promotees Johnson and Darius Garland. The Olympic-bound trio of Khris Middleton, Jrue Holiday and Devin Booker remain at the NBA finals. … The U.S. faces Argentina on Tuesday in Las Vegas.