What a difference nine days make. In barely a week, the Opals have transformed themselves from tournament disappointments to genuine medal contenders.

Australia’s women’s basketball team opened their Olympic campaign just over a week ago with one of the team’s worst performances in recent memory: 26 turnovers and 44% shooting accuracy saw them slump to a 13-point defeat at the hands of Nigeria. Having rebounded with subsequent group stage wins over Canada and France, Australia are suddenly red-hot in Paris. An 85-67 win over Serbia in their quarter-final clash on Wednesday morning has turned the heat up even more.

The Opals will face defending champions the United States in the semi-finals on Friday. One more win at the Bercy Arena and the Opals will play for gold ahead of the closing ceremony on Sunday, in one of the last medal events of the Games.

Alanna Smith and Jade Melbourne led the scoring for the Opals, with 22 and 18 points respectively. Jovana Nogic was Serbia’s most dangerous player, contributing 17 points and five assists. The win will taste extra sweet after the eastern Europeans downed the Boomers, the Australian men’s team, in overtime on Tuesday.

The Opals were once an Olympic powerhouse – winning consecutive silver medals in 2000, 2004 and 2008, followed by bronze in 2012 (and the team’s first and only World Cup triumph in 2006). But the team failed to reach the medal games at the past two Games, eliminated by Serbia in the quarter-finals in 2016 and bundled out by the United States in Tokyo. Serbia, on the other hand, are a relatively recent addition to the Olympic competition but began with a bang: winning bronze on debut in Rio and reaching the final four in Tokyo.

But any sense of an emerging team eclipsing a waning powerhouse was immediately dispelled on Wednesday morning, as physical defence and potent offensive movement gave the Opals an immediate advantage. There was a moment halfway through the first quarter that symbolised the Australians’ energised approach, with team veteran Steph Talbot leaping for an intercept as Serbia made a wayward pass. The move did not come off, Talbot earning a personal foul for her efforts. But it was a statement: the Australians would give no quarter.

Despite some dangerous plays from Fenerbahçe point guard Yvonne Anderson, the Opals largely contained Serbia in the first quarter and entered the initial break with a seven-point advantage. That lead only grew in the second quarter, thanks to some near-flawless shooting from Melbourne, and Australia went into half-time ahead by 16 points.

Any Serbian hopes of Australian complacency or profligacy in the third quarter were quickly dashed. Less than 24 hours before, the Serbian men had executed the biggest comeback in Olympic basketball history, recovering from a huge early deficit to beat Australia. But the traffic was all one way in the third: the lead growing once more to a 24-point advantage by the end of the quarter.

Serbia held firm in the final quarter, slowly eating into the Australian advantage, but it was ultimately too little, too late. The Opals rallied in the last minutes to see out an 18-point win.

Melbourne, who had one of her best games yet in the Opals shirt, said the Australians were aiming high. “We came in here with a goal to get to the semi-finals,” said the Washington Mystics guard. “Our next will be the gold medal match. We’ve ticked one off the list, but the job’s not done – we’re looking forward to the next one.”

The Opals will now resume their rivalry with the USA in another edition of the longstanding grudge match, an enduring rivalry in women’s international basketball. So often, the Americans have stood between Australia and Olympic or world cup glory.

Team veteran Lauren Jackson, who did not see any minutes against Serbia, said she was relishing another Olympic semi-final, her fifth following a glittering career. “We’ve had great tussles with [the Americans] over the years,” she said. “You never know what can happen on any given night. I truly believe this team is capable of big things.”