KAILUA, KONA, Hawaii — Craig Alexander won the Ironman World Championship on Saturday, making a late charge in the stifling heat to claim his second straight title.

The 36-year-old Australian completed the 140.6-mile endurance test in 8 hours, 20 minutes and 21 seconds, beating California's Chris Lieto by more than 2 minutes.

Britain's Chrissie Wellington earned her third straight women's title, finishing in a course record 8:54:02 — nearly 20 minutes ahead of Australia's Mirinda Carfrae. Wellington broke Paula Newby-Fraser's mark of 8:55:28 set in 1992 and finished 23rd overall.

Alexander and Wellington each won $110,000.

The triathletes had virtually windless conditions much of the day. They battled the unforgiving heat that radiated off the pavement and the ink-black, sun-baked lava fields.

Alexander, the first to defend the men's title since Timothy DeBoom in 2002, waved a small Australian flag and gave high fives in the home stretch. He walked the final steps, paused at the finish line, raised the ribbon over his head and roared as he flexed his muscles.

He was draped with leis before being greeted by his family.

"Daddy, those are nice flowers," his young daughter Lucy said.

Alexander stayed in the hunt in the 2.4-mile swim and 112-mile bike race before overtaking Lieto with about 5 miles left in the 26.2-mile run. Fighting off cramps, Lieto tried stay on Alexander's heels, but couldn't keep up.

Lieto made a strong move on the bicycle. He pressed hard heading up to the town of Hawi and took the lead from 2005 champion Faris Al-Sultan just before reaching the 60-mile mark.

Lieto started to pull away as he made his way back to Kona, taking a 5½-minute lead over Maik Twelsiek to start the run.

Meanwhile, the 32-year-old Wellington was alone for much of the race.

She was controlled and confident, easily beating last year's winning time of 9:06:23 and breaking the long-standing record of eight-time winner Newby-Fraser.

An emotional Wellington was speechless at the finish line.

"Mahalo," she said, using the Hawaiian word for "thank you."

She surged to the front with a dominating performance on the bike and opened up an 11-minute lead to start the run. She sailed the rest of the way on foot, leaving the women fighting for second place and passing several men.

Wellington began the bike in eighth place and quickly moved into second by the 10-mile mark, trailing Lucie Zelenkova. A few miles later, Wellington blew past Zelenkova along Queen Kaahumanu Highway for the lead and built a comfortable cushion over Canada's Tereza Macel by the turnaround.

After a bike split of 4:52:07, her lead grew to more than 17 minutes just 10 miles into the run.

Yvonne Van Vlerken, who finished second last year, pulled out of the race after having mechanical problems with her bicycle gears.

A field of 164 pros were among the 1,800 triathletes from 58 countries that began the race just as the sun rose above Mount Hualalai.