Sebastian Korda stared down Carlos Alcaraz on Sunday, sending the world No 1 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 No 1, 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 his historic Australian Open triumph 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.
The Spaniard stepped up his intensity to win five straight games. 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 to force Korda to serve for the match again, the American made no mistake, sealing victory on his second match point as Alcaraz sent a service return long.
WHAT 👏 A 👏 MOMENT 👏
— ATP Tour (@atptour) March 22, 2026
Look at what it means to @SebiKorda as he defeats World No. 1 Alcaraz on home turf! @MiamiOpen | #MiamiOpen pic.twitter.com/2xGOrM2oXj
"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.
"He's unbelievable in every aspect of his game, movement, volleys, forehand, backhand, there's nothing he can't do," Korda said of 22-year-old Alcaraz, whose Australian Open title made him the youngest man to complete the career Grand Slam.
Alcaraz, who fell in the semifinals at Indian Wells this month, was on the defensive early against Korda, who broke for a 5-3 lead in the first set and pocketed the set with an ace.
He broke Alcaraz again for a 2-1 lead in the second before the Spaniard's spirited fightback that ultimately came up short.
Korda will face either Spanish qualifier Martin Landaluce or 14th-seeded Karen Khachanov for a place in the quarterfinals.
Sixth-seeded Taylor Fritz broke big-serving compatriot Reilly Opelka once in each set to triumph 6-3, 6-4 in just 63 minutes.
Fritz served just four aces to Opelka's 10, but Fritz won 29 of 31 points behind his first serve and dropped just six points on his serve overall.
Fritz lined up a fourth-round clash with Czech Jiri Lehecka, who beat American Ethan Quinn 6-3, 7-6 (8/6).
RYBAKINA ADVANCES
World No 1 and defending women's champion Aryna Sabalenka, coming off her first Indian Wells title last weekend, headlined the night session against 72nd-ranked American Caty McNally.
In early women's action, Australian Open champion Elena Rybakina – seeded third despite moving up to No 2 in the world this week – moved smoothly into the last 16 with a 6-3, 6-4 victory over Ukraine's Marta Kostyuk.
Rybakina next faces Australian qualifier Talia Gibson, who knocked off another seed with a 6-2, 6-2 victory over 18-year-old 18th seed Iva Jovic.
Gibson, coming off an impressive run to the Indian Wells quarterfinals, had ousted former world No 1 Naomi Osaka in the second round.
Fifth-seeded American Jessica Pegula, runner-up to Sabalenka last year, reached the fourth round with a comfortable 6-2, 6-2 victory over Canadian Leylah Fernandez.
Former French Open champion Jelena Ostapenko, runner-up in Miami in 2018, held off seventh-seeded Jasmine Paolini 5-7, 6-2, 7-5, emerging victorious from a see-saw battle that saw the Italian charge back from 0-4 down in the third set, recouping two service breaks to level at 5-5 before Ostapenko put it away.
Ostapenko next faces 45th-ranked American Hailey Baptiste, who upset ninth-seeded Ukrainian veteran Elina Svitolina 6-3, 7-5.