Three semi-finals were held for both the men and women before finals due tomorrow.

The top nine athletes from each semi-final, plus the three next-best times, progressed.

It came in a sprint format in which athletes had to tackle a 750 metres swim followed by a flat 20 kilometres bike section and a concluding 5km run.

Tamás Tóth and Bence Bicsák each claimed home heat wins in the men's competition.

Tóth clocked 52min 39sec in heat one to beat Russia's Dmitry Polyanskiy, second in 52:39, and Brazil's Manoel Messias, third in 52:40.

Bicsák crossed in 52:27 in heat two to beat Norway's Jørgen Gundersen, second in 52:39, and France's Anthony Pujades, third in exactly the same time.

Matthew Sharpe of Canada then won heat three in 52:09.

Sylvain Fridelance of Switzerland and Vasco Vilaca of Portugal took second and third respectively after each crossing a second behind.

Emma Jeffcoat of Australia won the first women's heat in 59:17.

Zsófia Kovács of Hungary was second in 59:29 and Anabel Knoll of Germany third in 59:36.

Sophie Coldwell of Great Britain won a similarly tight heat two in 59:36.

She was awarded the same time as second-placed Taylor Knibb of United States while Portugal's Melanie Santos finished a single second behind the leading duo in third.

Roksana Slupek of Poland then won the final heat in 1:00:05 to beat Italy's Ilaria Zane, second in 1:00:12, and Hungary's Zsanett Bragmayer, third in 1:00:18.