Israeli Blessing Akawasi Afrifah stunned favourite Letsile Tebogo to win the men's 200 metres by a whisker in 19.96 seconds at the world under-20 championships in Colombia on Thursday.
Tebogo drew comparisons to Usain Bolt when he coasted to victory in the 100m in a junior world record time of 9.91 on Tuesday but the Botswanan's hopes of a sprint double were dashed by Afrifah in a thrilling final.
The 18-year-old, born in Israel to West African parents, stayed close behind Tebogo coming round the bend and a late surge saw him claim the title by six thousandths of a second in a photo-finish.
"I'm so emotional. I'm out of words," Afrifah told the World Athletics website.
"For a second, I thought 'Okay, I'm second, but I am very happy to be second to Tebogo'. I achieved my dream."
Tebogo, 19, was given the same time, which bettered the championship record he set in the heats on Wednesday, and said he was more than happy with his run after a busy week of competition at Cali's Pascual Guerrero Stadium.
"This is the best race that I have ever run in my life so far," he said.
"I'm really grateful for the performance and it's not everybody who can run these fast times, four days in a row."