In a match-up of the two teams tipped to meet again in the gold medal match on October 3, the US stamped their authority on the game in a dominant first half, using a suffocating 18-0 run bridging the first and second quarters to break the game open.
Down 51-33 at halftime, the Opals fought back impressively to win the second half 42-32, but the damage had been done.
Liz Cambage came of age for Australia, utilising her 204cm frame to finish with 18 points, seven boards and four blocks, while Lauren Jackson added 13 points.
But American superstar Diana Taurasi broke out of her slump to lead all scorers with 24 points, while centre Sylvia Fowles scored 15 points in the first half.
After trailing by as much as 24 points in the first half, the Opals closed to within 11 during a vastly improved third term, winning the quarter 24-21 with most of the starters resting.
They then closed to 83-75 on a Kristi Harrower three-pointer with 50 seconds left, but that was the final basket from either team.
While Opals coach Carrie Graf said prior to the game the result was irrelevant as both teams had already qualified for the quarter-finals, the loss means Australia face a tricky knock-out game against the host nation on Friday and the US have a far more comfortable date with Korea.
America's record in world championship games against Australia is now 9-0 since they first met back in 1967.
After just a handful of minutes the standard of basketball was already higher than in any previous game at Cez Arena and it was the Americans who took an early advantage courtesy of Fowles.
With the teams trading baskets and the US in front 14-13, Fowles keyed a quick 7-0 run to give them a 21-13 lead just over five minutes into the game.
Five straight Opals free-throws closed the gap to three points, but the US then shifted up a gear, ending the quarter with an 8-0 run for a 29-18 edge at the first break.
Their run reached 18 straight points in the second term before Jackson finally broke the drought from beyond the arc. Australia managed to steady the ship from there onwards, but the US were still worthy winners.
Australia hadn't shot below 40 per cent from the field all tournament before tonight, and although they were rock-solid in two-point territory, they went just four of 23 from down-town, an unusually low three-point shooting performance from an Opals line-up that has buried teams from that distance this tournament.
Australia now has a day off before they meet the Czech Republic in Karlovy Vary on Friday.
Earlier, French captain Celine Dumerc hit a driving lay-up on the buzzer to defeat Canada 49-47 as France tune up for the quarter-finals, while Belarus qualified for the last eight with a 74-70 victory over Greece that knocked the Greeks out of the tournament.
USA 83 (Diana Taurasi 24 points, Sylvia Fowles 15 points)
defeated
Australia 75 (Liz Cambage 18 points, Lauren Jackson 13 points)
USA Aus
1st Q 29 - 18
2nd Q 22 - 15
3rd Q 24 - 21
4th Q 11 - 18
