The brothers had arrived on the Italian island after attending a training camp in New Mexico, and while the day went ideally for 31-year-old younger sibling Jonny, the London 2012 and Rio 2016 champion Alistair, two years his senior, halted his race before the concluding run.

Earlier on a windy, sunny day Germany’s Marlene Gomez-Islinger won the women’s race to claim her first gold in this event, which this year involved the sprint format with a 750 metre swim, a 20 kilometre bike ride and a five kilometre run.

Brownlee won in 54min 48sec, with Switzerland’s Adrien Briffod second in 54:52, and Spain’s fast-finishing three-times world champion Mario Mola third in 54:59.

The Briton remained within striking distance of the lead throughout the swim and the notoriously steep bike section before he and Briffod pulled clear on the run, and he secured victory with his unanswerable burst over the final 300 metres.

"It was complicated on the bike because of the wind, and we were a large group," Jonny Brownlee, who won bronze at London 2012 and silver at Rio 2016 told World Triathlon.

"That’s not what I expected.

"In the run I felt really good.

"I know it’s easy to say that when you win, but I felt in control.

"I saw Alistair with about 1km to go and he said ‘When you go, make sure you mean it’ - and I made sure I did."

It was a timely win in what was the third race of the Tokyo 2020 Olympic qualification period after the World Triathlon Championship Series in Yokohama and the World Cup in Lisbon earlier this month, and with the next World Cup looming in the Brownlees’ home city of Leeds.

Norway's Kristian Blummenfelt - the winner in both Yokohama and Lisbon - was seventh in 55:25.

In the women's race, home favourite Verena Steinhauser replicated her bronze medal performance in this event last time, with Gomez-Islinger passing Switzerland’s Julie Derron, who had looked in control coming out of the second transition, with a few hundred metres to go.

"I tried to run very conservatively and had enough energy towards the end to do a good sprint finish," said Gomez-Islinger after winning in 1:00:51.

"The girls gave me a hard time on the hill but I’m proud of myself for what I did today and I put together a perfect race."

Derron was timed at 1:00.55, Steinhauser at 1:01.09, and France’s Audrey Merle fourth in 1:01.17.

Thirty-five athletes will race in the men's and women's triathlons at Tokyo 2020, with 26 coming from the individual world rankings.

Continental places, automatic spots for the host nation and Tripartite Commission places will complete the field.

The cut-off point is June 14 with only two events left before then.