A mix-up in qualification rules meant London 2012 champion Cheban initially missed out on a place in the final, before being reinstated in place of Czech paddler Martin Fuksa.

The 30-year-old then went on to claim gold, finishing in 39.279 seconds.

Cheban launched himself at the finishing line resulting in his boat capsizing.

"Maybe the first time I won the medal it was more emotional, but this time I knew what I should prepare for," said Cheban.

"I was preparing for a tough race and it was indeed that. 

"This race was much, much harder than the previous one."

Valentin Demyanenko of Azerbaijan won the silver with Brazil's Isaquias Queiroz dos Santos securing bronze.

Dos Santos, 22, became his country's first canoe sprint world champion in 2013 and has a remarkable back story.

At the age of five, he was kidnapped and offered for adoption before his mother managed to get him back, and at the age 10 he fell out of a tree after trying to catch a snake and lost a kidney.

In the first race in a busy morning of canoe sprint action, Germany's Max Rendschmidt and Marcus Gross won gold in the men's double kayak 1,000m final.

The pair led at the 250m mark after a strong start and controlled throughout as they finished in 3:10.781.

Serbia's duo of Marko Tomicevic and Milenko Zoric made a late charge but claimed silver, whilst Australia's Ken Wallace and Lachlan Tame were third.

In the second pairs race of the day, Spain's Saul Craviotto and Cristian Toro won the gold medal in the men's double kayak 200m.

Craviotto and Toro crossed the finish line with a time of 32.075, while the Great British duo of Liam Heath and Jon Schofield and Lithuania's Aurimas Lankas and Edvinas Ramanauskas won the silver and bronze, respectively.

Hungary's Danuta Kozak retained her K1 500m kayak title with an emphatic win at the Lagoa Stadium in the final race of the day.

The 29-year-old powered away from the field, in what was billed as a close competition, to finish in 1:52:49, nearly two seconds ahead of Denmark's Emma Jorgensen who was the youngest finalist at just 20 years of age.

New Zealand's Lisa Carrington claimed bronze in a close finish to add to her gold medal in the 200m kayak sprint.