Daniil Medvedev and Stefanos Tsitsipas were unable to cash in on the absence of tennis' 'Big 3' at the Miami Open as they crashed out of the event within hours of each other.
Hubert Hurkacz of Poland earned his first semi-final berth in a top-level ATP event on Thursday when he came back to shock the No.2 seed Tsitsipas.
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The 2-6 6-3 6-4 victory earned the No.26 seed a third-straight win when facing a top-five opponent, and just his second victory against the Greek in their eight meetings.
The upset further scrambled the draw after the top-seeded Medvedev lost to No. 7 Robert Bautista Agut on Wednesday night.
With Novak Djokovic, Rafael Nadal and Roger Federer all skipping the tournament, Medvedev and Tsitsipas were handed the perfect opportunity to take advantage.
But Medvedev fell to 0-3 against Bautista Agut in an 92-minute boilover on Wednesday.
The Russian mangled his racquet in anger after he lost serve to fall behind late in the first set, and little went right for him the rest of the way.
"If he broke a racquet, it's because he lost his patience," Bautista Agut said.
"I think I did some great things to put him under pressure and feel like this."
Hurkacz storms back to stun Tsitsipas
On Thursday, Hurkacz mounted an incredible comeback to send Tsitsipas packing.
The Polish player was serving at 0-2, 15-40 in the second set when he began his fightback.
He steadied his baseline game, while Tsitsipas became increasingly erratic and frustrated as the match progressed.
"I was very stressed these two weeks," Tsitsipas said.
"I felt like it was my opportunity. It's a very disappointing loss.
"Everything was under control. And suddenly, I don't know, self-explosion."
Hurkacz hit 15 aces and saved 10 of the 13 break points he faced. He'll climb in next week's rankings to at least 27th, a career high.
"I want to be as good as I can," Hurkacz said. "Hopefully, I can win some titles in the future."
Tennis fans were left in disbelief over the chaotic drama, with Alexander Zverev also falling earlier in the tournament.
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