An arduous journey driven by an audacious dream of competing at the Olympics finally bore fruit yesterday for sailors Griselda Khng and Sara Tan.

Competing at the 49er World Championships in Buenos Aires in Argentina, they finished 13th out of 44 boats - well enough to earn one of the three qualifying spots for Rio next year.

The pair have been campaigning for the quadrennial event since becoming partners in 2013. The 49erFX skiff is a new class making its debut at the Olympics next year.

"It's been a tough road," coach Fernando Alegre told The Sunday Times in a phone interview from Buenos Aires.

"The whole year has been extremely hard. The girls had to try to gain weight (for the boat), and they had a lot of catching up to do with people that were ahead of them."

The ideal combined crew weight for the 49erFX is between 125kg and 135kg.

Added Alegre: "They've worked really hard the whole time, with a very professional approach and we had a lot of people supporting us.

"It's been a difficult road but finally it was achieved."

Tan, 25, and Khng, 24 - the 2006 girls' world Optimist champion - are ranked 28th in the world, the highest-rated Asians.

They also finished as the top Asians at the world championships this time.

Their spot at the Rio Games, however, is not yet guaranteed. But they already have a sizeable lead over team-mates Cecilia Low and Kimberly Lim, who finished 26th.

The world championships was the first of two regattas earmarked by the Singapore Sailing Federation as nomination events. The second event, which bears a lower weightage, will be the Trofeo S.A.R Princesa Sofia regatta in Spain next March. The top pair with the lowest weighted point score after both regattas will be nominated to represent Singapore.

Singapore will have eight sailors competing in Rio, the most ever sent to an Olympics.

Other sailors have also clinched spots in the mixed multi-hull Nacra 17, the double-handed women's 470, men's Laser Standard and women's Laser Radial.

The previous high was in 2008 when the Republic was represented by six sailors - in the men's and women's 470, Laser Standard and Laser Radial.