America have finished top of the swimming medal table at every Olympics since Melbourne 1956, discounting some suspicious East German wins in the 1980s. But Australia lead the gold count with two night to go

Australia’s 4x200m relay team won gold to lead the swimming medal table (Getty Images)

Australia, queens of the pool. Their 4x200m freestyle relay team was bookended by this Olympics’ 200m champion Mollie O’Callaghan and 400m champion Ariarne Titmus. Between them, the 400m short course world champion Lani Pallister and the six-time relay world champion Brianna Throssell kept up the momentum, and given all that, perhaps the most remarkable part of this race was that it actually was a race, with USA and China finishing only a couple of body lengths back.

This was solid gold confirmation of the Australian women’s dominance in the pool, as if it were needed. All five of their swimming gold medals at these Games have been won by women, either as individuals or as a team.

But it was also a step towards a bigger goal, that of usurping USA as the No 1 nation in the pool. The last time the Americans failed to finish on top of the Olympic swimming medal table was 1988, when they were beaten by East Germany, whose athletes were pumped full of Turinabol. For USA’s last legitimate defeat you have to scroll back to the 1956 Games in Melbourne, where they were beaten by Australia.

Olympic swimming medal table after Thursday’s results

“There’s a reason the Americans haven’t been beaten since 1956,” Australian head coach Rohan Taylor told the Guardian before the Games. “They’re just extremely competent when it comes to the Olympics. This is where they step up – they have the depth, they have the numbers, they have the experience.”

That depth is borne out by America’s superior total medal count in the Paris pool, with 20 so far compared to Australia’s 11. But after this race, USA are behind in the colour that counts, gold, and time is running out to protect their crown.

There are still two more nights to come at La Defense Arena and the US team have some cards to play. The women’s 4x100m medley will be much be closer than this race, with Canada in the mix too. Bobby Finke is a gold medal contender in the men’s 1500m final, Katie Ledecky is favourite in the women’s 800m final, and the men’s 4x100m medley is also a target for the US.

But Australia still have bullets to fire too, particularly in sprinter Cameron McEvoy who goes up against Britain’s Ben Proud in the 50m freestyle final. McEvoy is the world champion and the pair shared exactly the same time in their semi-final on Thursday night.

Which could mean that it all comes down to one race, like the women’s 200m backstroke final. Australia’s Kaylee McKeown is the best backstroker in the world with four Olympic gold medals and four world titles. She is the reigning world champion over 200m but she comes up against two Americans: her perennial shadow Regan Smith, whose long list of silvers is mostly McKeown’s doing, and perhaps Smith’s unheralded teammate Phoebe Bacon too, given she qualified fastest for the final.

It will go to the wire. The US will finish with the most medals, but Olympic currency is gold and after this display of speed by O’Callaghan, Pallister, Throssell and Titmus, after nearly 70 years looking up at the USA, it is Australia who now lead the count.