The 31-year-old triathlete from Britain had a lead of about five minutes when her tyre went flat near the 145km mark of the 180km bicycle ride.

Air canisters she carried did not work, but Rebekah Keat of Australia came to her rescue.

Keat stopped, gave Wellington another canister, and the defending champion was on her way again.

It cost her about 10 minutes and the lead, which she quickly regained and held throughout the marathon run.

'Without it, I wouldn't have finished or would have finished way back with the age-groupers,' she said.

Her winning time was 9hr 6min 23sec. Yvonne Van Vlerken of Austria was second in 9:21:20.

Australia's Craig Alexander came from behind to win the men's title in 8:17:45.

The 35-year-old was 11th at the end of the bike ride, but ran a strong marathon to take the lead shortly after the 29km mark.

He said he drew on the support from former champions Dave Scott, Mark Allen and Scott Tinley, who encouraged him from the sidelines along the way.

'It was a thrill to see those guys out there,' said Alexander, who was second last year in his first Hawaii Ironman attempt.

The weather was much worse than last year, with the athletes having to deal with choppy seas in the 3.9km ocean swim, gusty crosswinds on the bike and heat during the bike and the run.

'It was a hard race,' Alexander said. 'But I was prepared for a hard day and had trained for wind.'

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