Competing in torrential rain for a place in the six-boat final, the duo were locked in a first-half tussle with Poland for second and third behind early leaders Ukraine.

As the Ukrainians faded Britain fought back impressively before winning by almost two seconds in 4min 7.74sec.

Ukraine's Dmytro Ivanov and Iryna Kyrychenko finished second with Michal Gadowski and Jolanta Pawlak of Poland third.

With the top eight boats securing places for their country in Rio de Janeiro, Britain are now guaranteed a Paralympic berth.

This comes after Yorkshireman Whiteley has trained on his own for more than two years in the hope a suitably-classified female would emerge to race at international level in the mixed double.

Teenager Rowles, who only took up the sport earlier this year after representing England in Para-athletics at the Commonwealth Games in Glasgow, fitted the bill perfectly.

“I’ve spent two-and-three-quarter years waiting for this moment," said Whiteley, who has recovered from bone cancer to compete.

"It does’t matter that it’s raining.

"Our goal here was to qualify and it feels great."

There was success for South Korea's Kim Sejeong in the women's single sculls as she won by over 20 seconds from Mariia Varlamova of Russia.

Brazil's Rene Pereira, Fabrizio Caselli of Italy, Igor Bondar of Ukraine and Johannes Schmidt of Germany were the four repechage winners in the women's single sculls.

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