MIAMI GARDENS, Fla. -- Tenth-seeded Jannik Sinner of Italy stunned top-ranked Carlos Alcaraz on Friday night in the Miami Open semifinals, rallying from a set down to beat the defending champion, 6-7 (5), 6-4, 6-2 in a three-hour thriller.
Sinner ended Alcaraz's winning streak at 10 matches before a packed house at Hard Rock Stadium.
Sinner's powerfully steady baseline game wore down Alcaraz, who appeared to be cramping early in the decisive third set while he also dealt with an apparent finger injury. He will lose the No. 1 ranking to Novak Djokovic.
Alcaraz said the cramping began after taking his five-minute bathroom break after losing the second set.
"When you stop for five minutes, I know it wasn't good for me,'' said Alcaraz, who committed nine double faults and 27 unforced errors. "I struggled with some problems.''
Sinner, the 21-year-old who made the Miami Open final last year but hasn't been past the quarterfinals of a major, will face fourth-seeded Daniil Medvedev of Russia in the championship match Sunday. Medvedev has beaten Sinner in all five meetings.
Alcaraz had been so dominant recently, he hadn't lost a set since February before Sinner's rally in the Miami humidity. The Alcaraz hype train has been so breakaway NBA stars Luka Doncic and Jimmy Butler showed up to watch the Spanish star from the teal seats.
Alcaraz also fought Sinner in Indian Wells in the semifinals, and it was a taut match but not quite like this. These two young guns are poised for a long and spectacular rivalry. Sinner's victory ended Alcaraz's hope of becoming the first man since Roger Federer in 2017 to win the Sunshine Double of Indian Wells and Miami.
"For sure it's one of the best wins,'' Sinner said. "I changed a couple of things from Indian Wells to here.'' Sinner declined to discuss the tactical switch but said he feels Alcaraz will likely adjust, too.
Medvedev beat fellow Russian Karen Khachanov 7-6 (5), 3-6, 6-3 on the same day Wimbledon announced Russians will be allowed back.
Medvedev has won 23 of 24 matches - the lone loss to Alcaraz - and is in his fifth straight final.
Also Friday, No. 15 seed Petra Kvitova beat unseeded Sorana Cirstea 7-5, 6-3 in the second women's semifinal. Kvitova will face Elena Rybakina in the final.
Alcaraz prevailed in the first set in a tiebreaker but that took a lot out of Alcaraz's 19-year-old legs. It included a wondrous, 25-stroke rally midway through the first set with Sinner up 4-2. Sinner crushed a backhand passing shot past a diving Alcaraz as a standing ovation ensued.
"The first thing that came to mind was that guy is invincible,'' said Alcaraz, who converted just 3 of 12 break points.
Between points early in the third set, Alcaraz was stretching noticeably and waved to the crowd for support. Alcaraz said the cramps started to ease and didn't blame it on the defeat.
"In the second set, I saw him struggling and I tried to push, especially in the first game,'' Sinner said.
Despite Alcaraz getting the second set back on serve, Sinner stunned Alcaraz in the ninth game, breaking him at love to go up 5-4 and then closing it out. Alcaraz had won 21 straight sets.
An ATP trainer came out to attend to Alcaraz midway through the second set, examining one of his fingers before the cramps set in.
Asked how he deals with this type of defeat, the Spaniard said, "After the match, like the 15, 25 minutes I can't talk to anyone. ... But after 20 minutes, I start thinking about positive things.''