Perri Shakes-Drayton beat the 400 metres hurdles Olympic champion for the second time in four days, but was still denied her first Diamond League win at the Aviva Birmingham Grand Prix.
The Briton, who failed to qualify for the final in London after her hamstring tightened in the warm-up ahead of her semi-final, crossed the line in second place behind Kaliese Spencer, but was upgraded to first when the Jamaican was disqualified.
Spencer was quickly reinstated, though, officials deciding her trail leg had not gone around rather than over the hurdle.
But Shakes-Drayton, who clocked 54.08 seconds, still claimed the scalp of London 2012 gold medallist Russian Natalya Antyukh, whom she also beat in finishing third at the Diamond League meeting in Lausanne on Thursday, and Olympic bronze medallist Zuzana Hejnova.
Her Olympic disappointment still hurts, however.
"I was heartbroken, I'm not going to tell fibs," the east Londoner said. "I'm kind of glad that it's over with as well because I can move on.
"I had anger, I had upset inside so I couldn't wait to get on the track again. I said I wanted to end my season on a high and at the moment it's looking that way because I'm running good times."