The much-hyped 'Next Gen' have so far failed to break Rafael Nadal, Roger Federer and Novak Djokovic's hold on tennis' biggest titles, but a new group of teenagers are hoping to show they can take over at the top of the game.
Carlos Alcaraz qualified for the Australian Open main draw aged just 17 earlier this season and at the French Open, now 18, won his first-round match this week.
The progression of Italian Jannik Sinner is being closely followed by tennis fans, but his compatriot and fellow 19-year-old Lorenzo Musetti is also threatening to race up the rankings.
With Federer 39, Nadal turning 35 on Thursday and Djokovic 34, there is a clear opportunity for the youngest members of the ATP top 100 to make their presence felt in the coming years.
But the same was previously said of the likes of Dominic Thiem, Alexander Zverev, Stefanos Tsitsipas and Daniil Medvedev.
So far, though, the only one of that quartet to win a Grand Slam title was Thiem at last year's US Open, when the Austrian was already 27 and with Nadal and Federer both absent and Djokovic dramatically defaulted in the fourth round.
Spaniard Alcaraz was born in 2003, the same year Federer won his first major title at Wimbledon.
He has already been tipped for greatness, and broke Nadal's record by becoming the youngest match winner in Madrid Open history last month.
He lost to his illustrious compatriot in the second round, but Nadal was upbeat about the teenager's future.
"He already has a great level of tennis today, but I really believe that he's going to be a fantastic player in the near future," said the 20-time Grand Slam champion after beating the young pretender in straight sets.
Rising stars like Alcaraz and Musetti are being increasingly moulded into future champions from a very young age.
Alcaraz, who warmed up for Roland Garros by winning a second-tier Challenger event in Portugal to break into the top 100, is trained at former world number one Juan Carlos Ferrero's academy.
On Thursday, he faces Georgia's 28th seed Nikoloz Basilashvili.
"From the moment he gets up to when he goes to sleep, we try to educate Carlos on all the recovery processes," his fitness coach Juanjo Moreno told atptour.com.
While younger players have traditionally struggled in best-of-five-set matches, Alcaraz is confident he is ready for the highest level.
"I trust a lot in my physical (conditioning), yeah. I could play a really, really good game during the whole match," he said after beating Bernabe Zapata Miralles 6-3, 2-6, 6-1, 7-6 (7/4) in Paris to at least match his run to the Australian Open second round.
- Musetti 'belongs' at top level -
Musetti announced himself to the ATP Tour late last year by beating Kei Nishikori and Stan Wawrinka en route to the Italian Open last 16 as a qualifier.
He started this season in Challenger tournaments, but has since reached two ATP semi-finals, losing twice to Tsitsipas in Acapulco and Lyon.
His defeat of 13th seed David Goffin in the Roland Garros first round was barely a shock, with it his sixth win from just nine matches against top-20 players.
"It demonstrates that I belong at this level, but there is still a long way to go," said world number 76 Musetti, who trained with Nadal ahead of the tournament, after seeing off three-time Grand Slam quarter-finalist Goffin 6-0, 7-5, 7-6 (7/3).
"Certainly training with Nadal is an exceptional experience that I will carry within me forever, but I liked the victory against Goffin because I demonstrated the right mentality, the one that takes you far."
Musetti will be the favourite against Japan's Yoshihito Nishioka in the second round on Thursday, showing how fast his stock has climbed despite making his Grand Slam debut this week.