World Number Three Alexander Zverev set up a mouthwatering ATP Finals rematch against Daniil Medvedev after beating Novak Djokovic.
It took Zverev more than two hours to see off Djokovic who was far from his best in the late-night semi final.
The Serb had a set point in the opener but failed to take it and Zverev showed his mental toughness by holding firm on the big points, taking the set 7-6 (4).
Djokovic's fans were given a glimmer of hope in set two as he managed to break the German's serve late in the set to take it to a decider. But the World Number One couldn't find the answers to Zverev's powerful groundstrokes and huge serve. His error-strewn display meant the comeback wasn't going to happen this time, and he went down 7-6 (4), 4-6, 6-3.
Zverev and Djokovic have both won two matches against each other this season. The Serb won the two Slam appearances while Zverev was victorious in their BO3 encounters.
Now, Zverev has an even trickier problem to solve: how can he stop his run of defeats against Daniil Medvedev? The Russian has won their last five matches, the most recent just a few days ago in the group stages.
It will be fascinating contest, not least because we are getting a glimpse into the future of what men's tennis will look like in the very near future.
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