American sprinter Sha'Carri Richardson was beaten over 100m for the first time this year at a meeting in Hungary on Tuesday.
Richardson never recovered from a poor start in Szekesfehervar and couldn't catch Julien Alfred, the Saint Lucia athlete who has been a sensation on the college circuit this season.
Alfred clocked 10.89sec to Richardson's 10.97.
It was a disappointing performance for Richardson who on Sunday beat the Jamaican Shericka Jackson, the fastest woman in the world this season, at the Diamond League meeting in Chorzow, Poland.
Richardson missed the Tokyo Olympics in 2021 after testing positive for cannabis and failed to qualify for the world championships in Eugene.
But she has shown newfound consistency this season and won the US title to make her one of the favourites for gold at this year's world championships in Budapest in August.
Olympic 400m champion Steven Gardiner recorded the fastest 400m time of the year, 43.74, in winning his event, racing home ahead of Rusheen McDonald of Jamaica, who clocked 44.03.