Simone Biles fell off the beam to miss out on a medal for the first time at the Paris Olympics as Alice d’Amato took gold.
The American, 27 – who won team, all-around and vault gold – lost her balance at the end of an aerial series and placed fifth, in a final where half of the gymnasts fell off the 10cm-wide apparatus.
It was a brilliant gold for Italy’s D’Amato, who won with 14.366. China’s Zhou Yaqin took silver with 14.100 and another Italian, Manila Esposito got the bronze with 14.000.
Biles, who has won three golds in Paris, has one more chance for another medal in Monday’s floor final (13:23 BST).
She looked unhappy with the crowd after her beam routine, speaking animatedly to her coach and her team-mate Sunisa Lee.
Shouts from an otherwise quiet crowd of “come on Simone” while she performed had drawn “shh” sounds from others.
In his BBC television commentary, former gymnast Craig Heap said: “I’ve never seen Simone Biles look so angry in my life.
“She was not happy. Something has gone on in the arena.
“Simone is not happy at all. It just goes to show she is a human being. All the other ladies in that final have made mistakes. She’s not invincible.”