New Zealand's Nicky Samuels blitzed a strong international field to win the Mooloolaba Triathlon ITU World Cup event on Sunday for her first victory at this level.

Samuels led from the start of the second-stage 40km bike leg and was never headed, finishing in 2:03:13 to cross the line 21 seconds clear of Australia's dual world champion Emma Moffatt (2:03:34) with Chile's Barbara Riveros Diaz (2:03:57) third.

Samuels and Switzerland's Daniela Ryf got a break on the rest of the field in the bike leg and when a downpour hit the field they opened up a decisive two-minute lead on the chasing group, which included Moffatt.

"As soon as it started raining that's when we got our gap in the lead," said Samuels, who now sets her sights on the World Championship Series opener in Sydney in two weeks and eventual selection for the 2012 London Olympics.

Performances in the Mooloolaba event count towards Olympic qualification.

"It's always good to have a good one at the start (of the year). Hopefully you can only get better throughout the season," said Samuels, whose previous best in an ITU World Cup event was bronze in Kitzbuhel, Austria in 2007.

"It's all been building up towards this year towards selection for the Olympics. So this is a key year for us," she said.

Moffatt was unable to match partner and coach Brad Kahlefeldt's first place in the men's event on Saturday, but her second place did earn her the Australian championship, as the first Australian home.

"I'm good at winning things without actually winning," Moffatt quipped to reporters after the race.

"Obviously I'd love to have a win but I'm always happy with second, it's better than third."

Moffatt was also relaxed about losing bragging rights at home in the wake of Kahlefeldt's victory over fellow Aussie Brendan Sexton.

"He never listens to me anyway," she said.

AAP