Athletics:It was third time lucky for American Allyson Felix who won Olympic 200 metres gold tonight after taking silver at the previous two Games.
After running solid until the bend, with Jamaican's Veronica Campbell-Brown and Shelly-Ann Fraser-Pryce still in medal contention, Felix lengthened her stride down the home straight for victory in 21.88 seconds.
"It's been a long time coming. I am so overjoyed," said Felix, who was runner-up to Campbell-Brown in 2004 and 2008 and lost her world title to the Jamaican last year. "I thought back to the disappointment in Beijing, it's been a long road, I never wanted to give up."
"I've wanted it for so long. This moment is really priceless."
Olympic 100 metres champion Fraser-Pryce of Jamaica took the silver in 22.09 ahead of American Carmelita Jeter, who won the bronze in 22.14.
Campbell-Brown faded down the home straight to finish fourth (22.38) with Olympic 400 champion Sanya Richards-Ross in fifth.
"We've been racing each other for years. I'm happy for her. I knew how bad she wanted it," Campbell-Brown told reporters.
A beaming Felix, who has a record eight world championship golds, jogged her lap of honour holding the US flag as the nation claimed three athletics golds in the session.
American Aries Merritt stormed to gold in the 110 metres hurdles, holding off world champion Jason Richardson to cross the line in a personal best time of 12.92 seconds.
The 27-year-old world indoor champion made the most of perfect conditions on a balmy evening at the Olympic stadium to run his fifth sub-13 second time in the last two months.
Merritt made an excellent start but was being shadowed by defending champion and world record holder Dayron Robles until the Cuban pulled up after jumping the sixth hurdle with what looked like a hamstring problem.
Merritt charged on and, with Richardson gaining on him with a late surge, dipped low to cross the line first in the fastest time in the world this year.
"The gold medal means everything," Merritt told reporters. "The U.S. haven't had a gold medal since Allen Johnson in 1996. It's phenomenal. To be here in this atmosphere is really special."
Usain Bolthardly had to break sweat tonight as he coasted into the men's 200 metresfinal where he will bid for an unprecedented Olympic sprint double-double.
Bolt(25) will be joined in tomorrow's gold medal showdown by compatriots Warren Weir and his most likely title rival Yohan Blake, as well as America's one representative Wallace Spearmon.
"I'm ready. This is my favourite event so I'm looking forward to it," Bolt told reporters after blitzing the first 100 metres to allow a gentle jog on the home straight for a heat- winning time of 20.18 seconds. "You can't work too hard, you've got the finals. That was the aim, you can't push too hard."
The world's fastest man sped to the 100m and 200m titles in Beijing in 2008 and on Sunday secured the former event once more in scintillating style. Victory tomorrow would make him unquestionably the sport's greatest ever sprinter.
Asked if he could break the 19.19 seconds world record he set in Berlin in 2009 Bolt said: "It's a possibility. I can't say but the track is fast so it's going to be a good race."
Although Spearmon, who finished third in Beijing in 2008 but was then disqualified for stepping out of his lane, is likely to battle it out with former European champion Christophe Lemaitre for bronze, Bolt did not rule out a Jamaican 1-2-3.
"It's going to be hard. Wallace Spearmon is there and he's been there before," said Bolt, who even managed a smile to camera once he was in the blocks at the start of his race. There's a lot of people there who are going to come and try and spoil the party so we'll see."
Blake, this year's fastest man, also looked impressive, running a strong bend before easing down for the night's best time of 20.01, with Spearmon and Lemaitre in hot pursuit.
"We had a tough one. We couldn't jog 20.1 (seconds) like some other guy. We were running," Spearmon said.
European champion and this year's Olympic 100 metres finalist Churandy Martina of the Netherlands also qualified.