As the Big Four's dominance at Grand Slam tennis tournaments continued at the Australian Open, former world No. 1 Lleyton Hewitt predicted Milos Raonic would be the next player to break the stranglehold.
Roger Federer's victory over Rafael Nadal at Melbourne Park on Sunday meant that the Big Four have collectively claimed 43 of the past 48 men's Grand Slam titles.
The three players not named Federer, Nadal, Novak Djokovic or Andy Murray to win a Major title in that time are Stan Wawrinka (2014 Australian Open, 2015 French Open, 2016 US Open), Marin Cilic (2014 US Open) and Juan Martin del Potro (2009 US Open).
And Hewitt expects Canadian Raonic, 26, to join that exclusive list, and be the next non-Big Four player to become world No. 1.
"At the moment you probably go with Raonic, only because he's No. 3 in the world," the two-time Major champion told The Straits Times last week in an interview organised by Mastercard on the sidelines of the Australian Open.
"He made the semi-finals here last year then made the Wimbledon final as well, so he's been very close to doing it. And because of his style of game - he serves so big that if he has one of those days when he's serving well and attacking from the baseline, he's hard to beat for anybody."
Raonic, a Wimbledon semi-finalist in 2014, dropped to No. 4 in the latest world rankings. Only Murray (No. 1), Djokovic (No. 2) and Wawrinka (No. 3) are above him.
Hewitt, 35, admitted that up-and-coming players are finding it difficult to win tennis' biggest prizes because of the increasingly physical nature of the game.
A bigger factor, added the retired tennis star, is that the top players are holding off retirement.
"A lot of the older guys are still hanging around and looking after their bodies so well and are still motivated to play well," said the Mastercard ambassador.
"(In the past) guys were probably retiring a bit earlier - once they got close to 30, they were retiring. Now we have guys - Nadal is over 30 now and you've even got guys like (30-year-old world No. 9 Gael) Monfils, (30-year-old world No. 18) Richard Gasquet, Rog who is 35."
Tennis great Bjorn Borg was only 25 when he played his last Major tournament. Two other former top-ranked stars, John McEnroe and Mats Wilander, did not win Major titles after the ages of 25 and 24 respectively.
The Big Four have arguably helped Hewitt remain the youngest ever men's world No. 1 - a feat he achieved as a 20-year-old in 2001.
The highest-ranked teenager now is Germany's 19-year-old Alexander Zverev, at world No. 22, while the last teenager to win a men's singles Grand Slam title was Nadal, who won the 2005 French Open at age 19.
But Hewitt has no doubts that Zverev, who took Nadal to five sets in the third round of the Australian Open, and Austrian Dominic Thiem, 23, are the future of men's tennis. Thiem became the first player last year to capture ATP titles on three different surfaces - clay, grass and hardcourt.
"I think Zverev - he's the real deal, a quality player," the Australian said. "Dominic Thiem, he's not that old either. I think he's going to have a big future."
- Lin Xinyi's trip to the Australian Open was sponsored by Mastercard
