Allyson Felix restored pride to American sprinting on Wednesday by claiming gold in the women's 200 meter and denying Jamaican rival Shelly-Ann Fraser-Pryce an Olympic double.
Felix used her elegant stride to good effect down the finishing stretch to pull clear of Fraser-Pryce, who won Saturday's 100m race while the U.S. runner missed out on a medal.
Carmelita Jeter joined her compatriot Felix on the podium by claiming third place ahead of Jamaica's two-time defending champion Veronica Campbell-Brown.
Felix had been forced to settle for silvers in 2004 and 2008 behind Campbell-Brown, but this time made no mistake as she added to her three 200m world titles with a fast time of 21.88 seconds.
"Finally, it's been a long time coming , I've waited so long for this moment, I'm just overjoyed," she told UK broadcaster the BBC.
However, Jamaica looks set to claim gold in the men's equivalent as defending champion Usain Bolt cantered into the final by winning his semifinal in 20.18 seconds.
Bolt has already made a successful defense of his 100m title in London and again the main opposition to another 200m triumph looks to be in the form of his teammate and training partner Yohan Blake.
Blake won the first semifinal in 20.01, jogging across the line, but Bolt is confident he will double up.
"No doubt about it," he told BBC Sport. "This is my favorite event and I'm really looking forward to it."
In other final action Wednesday, Aries Merritt won the 110m men's hurdles for the United States in a fast personal best time of 12.92 seconds.
His teammate Jason Richardson, the world champion from last year in Daegu, took silver in 13.04 second with Jamaican Hansle Parchment earning a surprise bronze in a new national record of 13.12 seconds.
Defending champion Dayron Robles of Cuba made a good start but pulled out at halfway with a hamstring injury.
The third track and field gold of the night for the U.S. went to Brittney Reese, who won the women's long jump with a leap of 7.12 meters.
Russian Elena Sokolova took the silver with 7.07m, with American Janay Deloach in bronze with 6.89m.
America's world 400m hurdles champion Lashinda Demus was denied Olympic gold as Russian Natalya Antyukh led from the start to win the women's event in a brisk 52.70 seconds. Czech hurdler Zuzana Hejnova claimed bronze.
Antyukh took bronze in the flat 400m at the 2004 Olympics and used that speed to triumph over the hurdles.