It is a 'dream come true' for the first American to win across 1,500 metres at the World Athletics Championships, since Mary Decker-Slaney did so in 1983.
Jennifer Barringer Simpson wins on a night full of surprises
DAEGU, South Korea // In a golden half hour for the United States, three Americans won world championship titles on Thursday, none more surprising than Jennifer Barringer Simpson claiming the first 1,500 metres victory since Mary Decker-Slaney in 1983.
Jesse Williams added the first high jump world title in two decades and Lashinda Demus ran the third fastest time in history to take the women's 400m hurdles.
At the end of the night, the United States led the medal standings with seven gold medals and 12 overall. Russia was closest with four gold and 12 in total.
On a day of surprises, double-amputee runner Oscar Pistorius reached his first major final, leading off South Africa's 4x400m relay team and helping them qualify with a national record. The South African team is to decide early on Friday whether the Paralympic star would still be in the starting line-up for tonight's final since they could also use Thursday's 400m hurdles bronze medallist, LJ van Zyl.
On a day when astonishment was commonplace, the face of Simpson told it all. She did not even figure in the top 10 of this season's performers before outpacing all the favourites and winning the first title for the US in the race in 28 years.
"I am supposed to say that I am not surprised," said Simpson, who had the 25th best time of the season heading into the worlds. "All I can say is that a dream has come true."
With her mouth open, Simpson sped past rivals on the finishing straight and then, with big eyes, looked at the giant screen facing her in Daegu Stadium to see if it really, truly, happened.
She closed her eyes and raised her fists in disbelief.
Williams, conversely, was as composed as can be in a nerve-racking event such as the high jump. He was perfect through the winning height of 2.35m, needing one jump less than Aleksey Dmitrik of Russia. Both failed three times at 2.37m to give the United States that first men's high jump title since Charles Austin at the 1991 world championships in Tokyo.
Elsewhere, Ukrainian Olha Saladuha won triple jump gold after defending champion Yargeris Savigne was forced to pull out of the final through injury.
The Cuban managed three attempts, just one of them valid, before, clutching her right thigh, she called an end to her title defence and left the way clear for European champion Saladuha to win her first world title.
Savigne appeared on the front of the programme for the sixth day of the Daegu championships and, like the cover stars on four of the previous five days, made an ignominious exit.
Dai Greene finally ended Britain's wait for a world championship gold medal with victory in the 400m hurdles in Daegu on Thursday.
The 25 year old went one better than silver medal winners Jessica Ennis and Mo Farah to claim victory in 48.26 seconds. The Welsh athlete passed Puerto Rico's Javier Culson in the final 20 metres before spreading his arms in celebration as he crossed the line.
"I have just been working so hard for this for many years," Greene told the BBC. "I've had my lows, but I always believed I could make it. I am just so pleased. I don't think it has sunk in yet to be honest."
Allyson Felix, the defending champion, eased into the final of the women's 200m.
Beaten to the gold medal in the 400m on Monday, the American admitted to feeling sluggish when returning to the more familiar discipline of the half-lap at the Deagu Stadium.
The 25 year old progressed comfortably enough despite finishing second in both her morning heat and evening semi-final, where she ran 22.67 secs but was beaten by Olympic champion Veronica Campbell-Brown.
"I just wanted to qualify easily and set myself up for tomorrow," Felix told reporters. "I wouldn't be human if I said I felt great."
Felix, attempting her first 200-400m double at a major championships, said she had spent the two days between her events taking it as easy as possible.
"I laid low, lots of ice bags, lots of treatment and lots and lots of movies," she said.
Asafa Powell pulled out of the Jamaican 4x100m relay team on Thursday because he has not sufficiently recovered from a groin injury.
Powell's agent, Paul Doyle, told The Associated Press it would be too much of a risk for the team if Powell were to pull up lame during the event in which Jamaica is a favourite for gold. The heats are Friday and the final is on Saturday.