15 years ago, Rafael Nadal and Kim Clijsters were ranked number one in the world.
A decade and a half earlier, it was Andre Agassi and Steffi Graf who reigned supreme.
Tennis changes a lot from year to year, never mind decade to decade.
What would the score be if Carlos Alcaraz faced prime Roger Federer?
Who is winning and in how many sets?
But what has changed the most in the last 15 years on the ATP and WTA Tour?
Appearing as a guest on the ‘Tennis Insider Club‘ podcast, Jim Courier shared his thoughts.
Jim Courier says the level in tennis today is ‘insane’
The former world number one explained how the game has changed since his playing days.
“The athletes are bigger and faster. So the game has gotten faster, the equipment, because it is lighter, and the string is more spinny, everyone has power. It does not matter if you are small, you have power now,” said Courier.
“The athleticism required in tennis today is so much greater than it was when I started playing on tour.
“It was getting fast by the time I was finished. We hit the ball hard, but [Pete] Sampras, [Boris] Becker, [Michael] Stich, [Richard] Kraijcek, [Goran] Ivanisevic, they are big servers, but their high end was 130mph.
“Now you have people who can hit 150mph.
- 2025 Wimbledon – Giovanni Mpetshi Perricard hit a 153mph serve
“It has gone even further. They would hit it with the equipment now, too, but they didn’t have it.
“The game is faster and more physical, but the players have more support now.”
Courier believes the players have the support around them to play at a higher level.
“They have better help to get ready before matches and come down after the matches. They have bigger teams, which seems to be helping players play longer,” he said.
“So, careers, even though it is more physical and more difficult, the players, I think, have better environments around them to keep going longer.
What is the best Grand Slam in tennis right now?
“For me, the tennis that I am seeing over the last 15 years, it’s unbelievably great.
“I can’t believe how lucky we are now as fans to watch it.
“Serena [Williams], and now Iga [Swiatek] and Aryna [Sabalenka]. The level is just insane.”
Courier isn’t wrong, as the stars of today continue to impress.
Records that once looked untouchable now look under threat…
Can anyone playing today break Serena Williams and Novak Djokovic’s Grand Slam records?
Serena Williams and Novak Djokovic hold the record for the most Grand Slam singles titles won in the Open Era.
Most WTA Grand Slam singles titles
| Rank | Name | Country | Grand Slam titles |
| 1 | Serena Williams | USA | 23 |
| 2 | Steffi Graf | Germany | 22 |
| T-3 | Martina Navratilova | USA | 18 |
| T-3 | Chris Evert | USA | 18 |
| 5 | Margaret Court | Australia | 11 |
Most ATP Grand Slam singles titles
| Rank | Name | Country | Grand Slam titles |
| 1 | Novak Djokovic | Serbia | 24 |
| 2 | Rafael Nadal | Spain | 22 |
| 3 | Roger Federer | Switzerland | 20 |
| 4 | Pete Sampras | USA | 14 |
| 5 | Bjorn Borg | Sweden | 11 |
23 and 24 Grand Slam titles are mightily impressive tallies that, when set, looked unbeatable.
Now, not so much!
In women’s tennis, two players look well-positioned to challenge Williams.
Iga Swiatek (24) is a six-time Grand Slam champion and has enjoyed a spell of dominance at the French Open.
If she can rediscover the clay-court form that saw her win four Roland Garros titles, it won’t be long before she reaches double-digit Slams and starts applying pressure to Williams.
World number one Aryna Sabalenka (27) is another potential contender.
Despite ‘only’ winning four Grand Slams, the Belarusian has been, by far, the best player at the major tournaments over recent years.
Aryna Sabalenka at Grand Slams since 2023
- W – 4
- F – 4
- SF – 3
- QF – 1
If she can improve her record in Grand Slam finals (1-3, since 2025), then Sabalenka may just make a late charge towards Williams’ record.
On the men’s side, Carlos Alcaraz and Jannik Sinner are the most likely challengers to Djokovic’s Grand Slam record.
It’s the Spaniard who is closest, having already won seven Grand Slams at 22.
The already-legendary Spaniard is on pace to break Djokovic’s record and is the youngest player to complete the Career Grand Slam.
If he can remain injury-free, Alcaraz may well retire as the greatest tennis player of all time, taking the Serb’s record in the process.
Only time will tell, though, and the likes of Alcaraz, Sinner, Sabalenka, and Swiatek won’t want to concern themselves with records just yet.
They’ll want to stay focused and turn their attentions to the next Grand Slam, the French Open.
The 2026 French Open begins on Sunday, May 24.
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