Boris Becker has thrown his backing behind "the king" Novak Djokovic ahead of his final tilt at the calendar Grand Slam in 2021 at the US Open.
The world number one is now just one match away from securing the remarkable feat, having already won the Australian Open, Roland Garros and Wimbledon so far this season.
Standing between Djokovic and the incredible achievement is second seed Daniil Medvedev, who has vowed to throw everything he possibly can at the Serb in what could be a legendary final.
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Becker has given his full support to Djokovic, who he used to coach, while fellow Eurosport expert Mats Wilander has also given his thoughts ahead of Sunday's showpiece.
"Long live the king! He is an incredible guy, an incredible player," Becker told Eurosport.
[The semi-final] was a special day, a special night. It's history in the making. Novak Djokovic is still about to rewrite the book.
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"He has the most important match of his life ahead. He is treating it like it's his last match. That's all you can say about it. He is 34 years old, his opponent on Sunday is only 25 - you have to put that all in perspective.
"I think for him it's about the last match of his life - and that's how he'll go in."
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Wilander added: "Of course, Novak is the favourite but this is the match I wanted to see. I wanted to see Novak tested and tired in the finals.
"Do I want to see him win? That is up to him. But I want to see a long match and a predictable physical match and Daniil Medvedev is the perfect opponent to take this on.
"This is a dream final for me and, with Daniil talking about leaving his heart on the court, that is huge and the crowd will be with him until Novak is close to history, I believe."
Not only can Djokovic clinch the calendar Grand Slam with a victory on Sunday but he can also move ahead of his great rivals, Roger Federer and Rafael Nadal, with a 21st Grand Slam singles title.
As for Medvedev, the Russian has reached two major finals previously, including at Flushing Meadows in 2019, and he will be anxious to go one step further than he could at Melbourne Park against Djokovic earlier in the season.
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