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Video - Jones cruises to breastroke win
Australia's Leisel Jones claimed gold in the women's 100m breaststroke final in Beijing making up for her heartbreak in the Olympics four years ago.
The world champion and record holder missed out on an Olympic title in Athens but was more than a body length clear as she set a new Olympic record.
She touched home in one minute 5.17 secs ahead of American Rebecca Soni with Austria's Mirna Jukic third.
Jones, 22, was just eight 100ths of a second outside a new world best.
A tearful Jones said victory at the Water Cube had made up for her traumatic campaign at the last Olympics in Greece which almost made her give up the sport.
In 2004 she came third in the 100m and second in the 200m breaststroke despite being favourite.
"It has been a long journey, there's a lot of relief that the training was definitely worth it," she said.
"I was really about to quit after Athens and I was very, very (close) to giving up the sport, I just didn't enjoy doing what I was doing.
"Over the past four years I've really found some enjoyment again, and I never thought I'd be here. I thought I was just deemed to be a bronze medallist."
Jones added: "I am delighted, I couldn't care less about the time.
"An Olympic gold is an Olympic gold, the time, the race, none of it matters - it's all about the gold.
"I've got so much more growing to do, and more learning. I've only been working with my coach Rohan Taylor for a year and I think I've got so much left in me.
The Australian is the first swimmer to win the double breaststroke gold at two consecutive world championships and she will be the one to beat in the 200m breaststroke heats which get underway on Wednesday.
Her success was the third gold won by Australia at the Water Cube, all by women, following wins by Libby Trickett in the 100m butterfly and Stephanie Rice in the 400m medley.