BMX World Champion Caroline Buchanan won a nail-biting final in the third round of the UCI BMX Supercross World Cup in Berlin on Saturday to begin her Olympic qualification process.

The 23 year old from Canberra began the first straight in second place with very little chance of overtaking the strong London Olympic champion, Mariana Pajon of Colombia, on a track known for limited passing opportunities.

But Buchanan pounced in the last turn to edge out Pajon, winning her second World Cup event of the season.

An emotional Buchanan was relieved as it marked the start of the point tally towards the 2016 Rio de Janeiro Olympics.

The current four cross world champion put her winning move down to skills she had acquired in mountain biking.

“It’s been a tough week but you know, all those years of mountain biking paid off,” said Buchanan.

“I actually practised that move earlier in the week but I knew it was going to be risky.

“Luckily for me it wasn’t too wet. My knee was almost scraping the ground I was that low and tight.”

Buchanan now has a sizeable lead in the women’s standings with a 100-point advantage over Dutch champion, Laura Smulders.

Double Olympic champion Maris Strombergs of Latvia dominated the men’s race but current world champion, Liam Phillips of Britain, remains on top of the series.

Anthony Dean from Adelaide was unlucky to crash out in the quarter-finals.