Australia won the mixed relay at the cycling worlds in Kigali on Wednesday after edging France and Switzerland in a nail-biting finale.

The Australian men Luke Plapp, Michael Matthews and Jay Vine were on their feet cheering as Felicity Wilson-Haffenden, Brodie Chapman and Amanda Spratt raced up the last hill of the closing leg of the relay win.

Having won the event last season, Australia successfully defended their title with limited preparation on the 42.4km course just five seconds ahead of France and 10s ahead of Switzerland.

"It's not often we get the chance to ride with a full Aussie team," said top men's rider Matthews, who races most of the year with his professional team Jayco.

"We only arrived a couple of days ago and we didn't ride out there on the roads until yesterday," he said, explaining the Australian national team had arrived for the elite road races that will be contested at the weekend.

"Today it all came good," beamed Matthews, known in the team as 'Bling' due to his penchant for diamond earrings.

- Bigger every year -

The Aussie men had ended their loop about 40sec ahead of France, but on a punishing course the women had to dig deep.

RTL

There was a feel-good vibe on the mixed relay podium / © AFP

The Aussie women were dragged gasping from their bikes after going full gas at altitude and with high humidity in a race that culminated with a tense countdown to see if they could stay in front of France.

"I knew it was going to be like hell, Brody was strong and I held her wheel. I could hear them (the men) screaming 'sprint, sprint, sprint' coming to the close," said Spratt.

French prodigy Paul Seixas was riding on his 19th birthday.

"It's a good sign for the future," said the teenager tipped to win the Tour de France one day. "Now I need to get ready for Sunday," he said of the epic 265km race with 33 climbs.

Swiss all-rounder Marlen Reusser won the women's time-trial gold on Sunday and led the team to third on Wednesday despite a damaging mechanical incident that likely deprived them of gold.

Combining men and women, the mixed relay was introduced in 2019 at the Yorkshire worlds, with three male riders completing a lap and the women going down the starters ramp when the men finish theirs.

"Every year this event gets bigger with more and more people watching," silver medallist Juliette Labous said. "Long may that continue."

There were 16 nations riding Wednesday with five of them from Africa -- Benin, Ethiopia, Mauritius, Rwanda and Uganda.