CYCLING - MTB: Australian mountain biker Rebecca Henderson has all but cemented Olympics selection after her maiden World Cup podium result.

The Glasgow Commonwealth Games bronze medallist and London Olympian finished third on Sunday at the opening round of the cross-country World Cup series in Cairns.

Henderson has also won the national and Oceania cross-country titles this year.

"Hopefully I have booked my ticket to Rio but anything further than that I don't want to say anything," she said.

With two World Cup events to go before the Olympic squad is named Henderson is the highest ranked Australian and looks set to grab the lone women's spot for her country.

Henderson dropped Canadian two-time world champion Catharine Pendrel on the last of six laps at Smithfield Regional Park.

Danish champion Annika Langvard won ahead of Switzerland's Linda Indergand after they went clear on the second lap.

Henderson said riding with Pendrel had been a major boost.

"Early in the race I wasn't backing myself, I was waiting for most of the field to catch me," she said.

"Catherine then caught me and I just tried to follow her as best as I could.

"Then on the last lap I thought it was now or never.

Pendrel in turn praised Henderson's performance.

"She earned that spot today and was on fire - (she) will do Australia proud this summer," Pendrel said.

But it was not such a good day for Henderson's partner Dan McConnell.

The two-time Olympian, who also won bronze in Glasgow, had two punctures on Sunday and they cruelled his chances.

McConnell made a strong start in the men's seven-lap race, but also struggled physically.

He was the first Australian finisher in 31st place.

Switzerland's four-time world champion Nino Schurter won ahead of French pair Maxime Marotte and Julien Absalon.

AAP