MELBOURNE: Over the past two decades, the 'Big Four' have collectively won 69 grand slam championships, firmly dominating the tennis world.
It was a time when few players managed to break through their dominance, with many talented contenders, such as David Ferrer, Juan MartÃn del Potro, and Jo-Wilfried Tsonga, all denied a taste of championship glory.
But as technology advances and younger players grow stronger and more dynamic, the question remains: will we see another 'Big Four' era?
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John Millman retired in 2024. Â Getty
"History would suggest no because that's why these (four) are constantly debated as the greatest of all time," retired Australian cult hero John Millman exclusively told Wide World of Sports.
"That's not to say it can't be done."
Roger Federer, Rafael Nadal, Novak Djokovic, and Andy Murray ruled tennis for the majority of the first quarter of the 21st century.
Djokovic leads the pack with 24 titles, followed by Nadal with 22, Federer with 20, and Murray a long way back with three, plus an Olympic Games gold medal.
Their dominance began at the 2003 Australian Open and continued for 20 years, with Djokovic, who is currently world No.7, the one man left standing.
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Millman, who turned pro in 2006 and retired last year, said it was a challenging era to compete in.
Throughout his career, the 35-year-old faced the tennis giants many times, with one of his most memorable moments coming in 2018 when he pulled off a huge upset by defeating Federer in the fourth round of the US Open.
Millman advanced to the quarterfinals but ultimately lost to Djokovic, who went on to win the championship.
"It was a privilege to share the court with some of the greatest we've ever seen in the sport," Millman said.
"In another sense though, it was a real challenge because I think we kind of lost for a while that unknown player making their breakthrough.
"It made it extremely difficult to win a grand slam, not to say I would have won (one)… It just made it (hard) for slightly lesser players to go for really deep runs at grand slams because the reality was (to win) a grand slam, you'd have to go and beat at least two of those big players."
Novak Djokovic at the Australian Open in 2024. Â Getty
New generation breaks through
There's been no shortage of talent at this year's Australian Open, with a handful of unseeded players pulling off unbelievable upsets.
Brazillian teenager, Joao Fonseca, won his first-ever grand slam match on Tuesday defeating world No.5 Andrey Rublev, in straight sets.
Meanwhile, 19-year-old Jakub Mensik sent world No.6 Casper Ruud packing after defeating him in four sets.
American qualifier Learner Tien, also 19, advanced into the fourth round after overcoming world No.5 and 2021 US Open champion Daniil Medvedev in a thrilling five-set match.
Twenty-year-old Alex Michelsen also defeated Stefanos Tsitsipas in his first-round clash and then world No. 19 Karen Khachanov on Saturday.
Millman acknowledged there's always talk about the next generation, but he also noted something seemed to be shifting in the tide.
He said there was so much talent rising.
"I remember when it was Agassi and Sampras (retiring) and people were saying it's the end of an era," he said.
"Then all of a sudden Roger and Rafa come through and people thought that those two were the ones that were going to dominate and then Novak started to announce himself.
"We are seeing Alcaraz and Sinner, and even a few other names that are really knocking on the door. Even Fonseca and these next-generation players.
"They are really talented."
Switzerland's Roger Federer left, and Spain's Rafael Nadal at Wimbledon in 2008. AP
Millman said the next decade would be an exciting time for the tennis world, as younger generations turn pro younger, and older generations play older.
"During my time, there were a couple of freaks that came through, but generally speaking, I think it maybe took some of the players a little bit more time to really establish them on the tour," he said.Â
"But now we're seeing this younger generation coming through without playing without fear, hitting the ball bigger.
"They're fearless fighters and I think it makes for really, exciting tennis, and that's not to count out some of these guys that."
