Eventually, the dominance of Novak Djokovic, Rafael Nadal and Roger Federer will end. Not even the all-time greats can escape the clutches of Father Time.

But for how much longer will the ‘Big Three’ rule the tennis world with an iron fist and which players are most likely to break up the party? Asked to contemplate those questions, Andy Murray said to circle your calendar for 2021 and that the disrupters will most likely come from players currently aged 22 or younger.

"I can see something happening in the next couple of years. Maybe the next 12-18 months I don't quite see it. But in 18 months to two years I think we'll see some changes up there,” Murray told ATPTour.com.

"I think it will mainly come from the younger ones. That's not to say that some of the older guys couldn't potentially win a Slam. I just don't see one of them becoming dominant. Potentially some of the younger guys get up to the top four or five in the world and stay there for a long period.”

Djokovic, Nadal and Federer have combined to win a staggering 160 ‘Big Titles’, comprising 54 Grand Slams, 95 ATP Masters 1000s and 11 Nitto ATP Finals. Murray was once bracketed in the ‘Big Four’ with the legendary trio, with 14 Masters 1000s, the 2016 year-end No. 1 Ranking and Nitto ATP Finals title, two Olympic singles gold medals and 45 singles titles.

Murray believes that Felix Auger-Aliassime, 19, reigning Next Gen ATP Finals champion Stefanos Tsitsipas, who turns 21 Monday, and Alexander Zverev, 22, are the players most likely to entrench themselves at the top of the game for an extended period.

"I like Felix. I like his game; physically he's very strong and he looks good mentally," Murray said. "He's still young so he'll need a little time. Tsitsipas has a really nice game; he's a good athlete and his personality is great. He's fun to watch. He has an all-round game that allows him to play well on all surfaces, which is important if you want to get up there and stay up there.

"Obviously Zverev has a lot of potential and he's won the most of the young guys. If you have a few bad months it's easy for people to forget that and start writing you off. But he's a young guy who can improve a lot.

"They would be the three right now. But there could be 17-, 18-year-olds out there who I haven't seen play much who could break through.

"Dominic Thiem has been in Slam finals and is improving all the time. He's got a great work ethic and a big game. I see him coming through and he could potentially win majors. But in terms of dominating, I think the guys at the top will stay around a little too long for that to happen."

Murray next week is set to return to singles competition for the first time since his emotional five-set first-round defeat to Roberto Bautista Agut at the Australian Open, after which he underwent a second surgery on his right hip. Murray returned to the ATP Tour in June, when he partnered Feliciano Lopez to the doubles title at Queen’s. Since then he has also played doubles at Eastbourne, Wimbledon, Washington and Montreal.

In Cincinnati he will play Richard Gasquet in the first round. The winner will meet fourth-seeded Thiem.

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