MIAMI - Sebastian Korda stared down Carlos Alcaraz on Sunday, sending the world number one crashing out of the Miami Open third round 6-3, 5-7, 6-4.
Korda, ranked 36th in the world, notched his first victory over a world number one, sending Alcaraz to his second straight early exit in Miami following defeat to 55th-ranked Belgian David Goffin in the second round last year.
Since that defeat, Alcaraz had built a remarkable 73-6 record, including a 16-0 start to 2026 that included an Australian Open triumph to complete a career Grand Slam and a title in Doha.
It looked like Korda had missed his chance to spring the upset when he served for the match at 5-4 in the second set and was broken at love.
Alcaraz won the next two games to force a third set, part of a run of five straight games for the Spaniard.
But Korda didn't buckle, and it was the American who seized a break for 4-3 in the third when Alcaraz sailed a forehand wide.
He held his next service game with confidence, slamming down an overhead winner on game point and after Alcaraz held serve Korda served for the match again, this time making no mistake.
"It feels great," said Korda, who has been ranked as high as 15th in the world but has endured two seasons disrupted by injuries.
"I took the scenic route, that's for sure -- a little more stress than I would want but happy with how I played, happy with how I stayed with it."
Alcaraz said Korda played an "incredible" match.
"A lot of tight, tight moments that I just didn't make the most of it," Alcaraz said. "I think he was better on those points, on those moments. I would say that was the key of the match."
Korda will face Spanish qualifier Martin Landaluce for a place in the quarter-finals after Landaluce ousted 14th-seeded Russian Karen Khachanov 6-3, 7-6 (7/2).