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Video - Rice earns second medley gold
Australia's Stephanie Rice pipped Zimbabwe's Kirsty Coventry in a stunning 200m individual medley final to claim her second gold of the Games.
Rice won in a new world record time of 2:08.45 just three days after she clinched gold in the 400m medley, when she also edged out Coventry.
The 20-year-old becomes the first Australian to win swimming's 200m and 400m medley double at the Olympics.
American Natalie Coughlin won the bronze, while Katie Hoff was fourth.
It was another disappointing race for Hoff, who took the bronze in the 400m medley when she had been hot favourite to win.
In a virtual re-run of the 400m medley, Rice had another stroke-for-stroke battle with Coventry before just out-touching her at the wall, lowering her own world record by 0.47seconds.
A delighted Rice told BBC Sport: "It really hasn't sunk in for me yet, what has happened at this meet.
"It was great for me to qualify next to Natalie Coughlin because she takes it out so hard.
"And I knew Kirsty Coventry would be there all the way, so I tried not to look at her and just concentrated on what I was doing."
It was Australia's fourth gold in the pool - all of them claimed by the women's team.
And Rice will have a chance to claim her third gold on Thursday when she takes part in the women's 4x200m relay.