Tennis fans were left stunned on Sunday after Alexander Zverev shocked Novak Djokovic to reach the decider at the ATP Finals.
The World No.3 produced a performance for the ages to topple the World No.1, prevailing 7-6(4), 4-6, 6-3 to advance to a showdown in the final with Daniil Medvedev.
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Zverev secured the vital break in the deciding set to go up 3-1 and wouldn't relinquish it.
Djokovic had breezed through to the last four without dropping a set as he chased a record-equalling sixth title and a first for six years.
But third seed Zverev, who ended the World No.1’s hopes of a Golden Slam by beating him at the Tokyo Olympics, got the better of Djokovic again.
Zverev knows he has the weapons to beat Djokovic and that confidence shone through as he saved a set point at 5-6 in the opener before playing an exceptional tie-break.
A sloppy game early in the third was uncharacteristic for Djokovic, and Zverev held firm on his own serve to clinch a fourth career win over the Serbian.
"I played a bad game and this made the difference in the third set," Djokovic said.
"It’s normal, you always decide on a few points against a champion like Zverev. No matter what, I had fun".
The stunning performance left tennis fans and commentators in disbelief.
Just like in the Olympics, Novak Djokovic's 2021 season ends with a 7-6, 4-6, 6-3 loss to Alexander Zverev in the semis of the ATP Finals. Crazy how well Zverev plays against Novak and how poorly he plays against Medvedev. But he gets another chance in the finals tomorrow.
— Dan Wolken (@DanWolken) November 20, 2021
Zverev was actually insane tonight. This was quality tennis for the ages! Will be super pumped going into tomorrow's final.
— Paul Adedoyin (@ThegentlePaul) November 20, 2021
— Double Fault 🎾 (@DoubleFault10) November 20, 2021
Oh what a performance Zverev. 👏🏿.. Downs world No. 1 Novak Djokovic 7-6,4-6,6-3.
A truly golden year
— Latifat Adebayo Ohio (@Phatill) November 20, 2021
5-5 30-40 down, Novak Djokovic hits the most ridiculous serve and half volley pick up. It’s as clutch as you can get 🔥
Zverev actually winning more of the baseline exchanges. Djokovic having to come up with the other intangibles in his versatile skillset to win this match
— Vansh (@vanshv2k) November 20, 2021
The scheduling didn’t make sense. That being said, Zverev played very well and will take nothing away from that. As for Novak, another insane year!
— Hazmat Chamiv ➐ (@SportsAvidFan) November 20, 2021
Alexander Zverev and Daniil Medvedev in final
Earlier, Russian World No.2 Medvedev produced a commanding straight-sets victory over Casper Ruud in the other semi-final.
Medvedev cruised through after wrapping up a 6-4 6-2 win in one hour and 20 minutes in Turin.
The World No.2 will face Zverev as he aims to become the ninth different player to successfully defend this title.
The US Open champion took early command, breaking in game three and holding before serving to love to take the opening set.
He did not offer up a single break point against Ruud, who he had beaten in both of their previous meetings.
Medvedev cruised through the round-robin stage of the season-ending tournament with wins over Hubert Hurkacz, Zverev and Jannik Sinner before dispatching Ruud.
"I think all the matches were a great level. Different opponents and different styles," he said.
"I managed to win all the matches. It was not an easy match (today).
"When you are in the final you can't complain, so I am just looking forward to tomorrow and hopefully I can have my best match."
World No.8 Ruud was aiming to become the third debutant to lift this trophy in five years after Grigor Dimitrov (2017) and Stefanos Tsitsipas (2019).
However the Norwegian, who squeezed past Andrey Rublev on Friday, was broken twice in the second set as Medvedev surged into a 5-2 lead, before serving out to complete a ninth straight win at this event.
Medvedev was asked if he, Djokovic and Zverev are the new "Big Three" - the term used for the way Roger Federer, Rafael Nadal and Djokovic have dominated the game for so many years.
Djokovic won three of the four grand slams this year, Medvedev took the other and Zverev won gold at the Tokyo Olympics.
"I don't want to say the Big Three but we are definitely right now at this moment the top three in the world," Medvedev said.
"It's easy (to figure out) in tennis because it's rankings."
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