The 'new top four' ahead of the 2022 season are Novak Djokovic, Daniil Medvedev, Alexander Zverev and Stefanos Tsitsipas, according to Eurosport expert Mischa Zverev.
Zverev won the ATP Finals for the second time on Sunday as he defeated Medvedev, the defending champion, in straight sets in Turin. The German came through to win 6-4 6-4 in one hour and 15 minutes to secure a tour-best sixth trophy of the year and end a five-match losing run against his opponent.
It was the world number three’s 59th victory of a highly successful season as he posted a 32-4 record since his Olympic Gold triumph in Tokyo to suggest he will be a major force in 2022, and his brother Mischa believes he is now part of a 'new top four'.
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"Compared to his last ATP Finals victory in 2018, he plays better, more mature, more intelligent and more complete in the overall package," Zverev told Eurosport. "He is the best Zverev there has been so far, but he can get even better.
”He has improved his volleys a lot, he also reads the game better, he knows when to attack or retreat. The selection of his strokes has also got better and he's moving well, very intelligently, at the moment. Against Medvedev, he found an excellent balance and correctly assessed when he needed to move forward and play calmly. There were a lot of tempo changes in the game, but it was all controlled.

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”Don't forget Tsitsipas, he was unbelievably strong for half the year. I also believe that someone like Rublev can annoy the other players. We also have to wait and see how things go with Nadal in the coming year. Is he coming back or not? How does he play the clay court season?
From my point of view, the new top four are Djokovic, Medvedev, Sascha and Tsitsipas. That's just my feeling; that can, of course, still change.
"It is mathematically possible to become number one without a Grand Slam title, but it is very unlikely. In the last 20 years, I think only Marcelo Rios has managed to get to the top without a Grand Slam victory.
"There are people who win a Grand Slam but have never won a Masters. You can then say that it was a lucky coup, but if you've already won a number of Masters and twice the ATP Finals, then that's not lucky.
"Sascha is one of the 10 players who have become world champions [ATP Finals] more than once. This list includes players like McEnroe, Borg, Becker and Sampras.
"From a purely statistical point of view, it should be enough for a Grand Slam victory. I don't want to rely too much on the past, but rather see how Sascha can develop further in the future."

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