The French Open semifinal between Roger Federer and Rafael Nadal comes 15 years after their first match against each other.
For tennis' sake, maybe this won't be their last meeting with a lot on the line. Given that Federer is 37 and Nadal 33, who knows?
Then again, why write either of these guys off now?
They've faced off 38 times in all, and even if it's not been the most-played men's rivalry in the half-century of professional tennis — it's third, trailing Nadal vs. Novak Djokovic (54), and Federer vs. Djokovic (47) — it sure is tough to top in terms of significance, storylines and contrasting styles.
Friday's showdown will be the sixth installment of Roger vs. Rafa at Roland Garros, always in a semifinal or final, but first there since 2011. Not coincidentally, that was also the last time the top four seeded men were the last four in the draw in Paris. After No. 2 Nadal and No. 3 Federer finish (weather permitting, of course; the forecast called for rain), they'll be followed in Court Philippe Chatrier by No. 1 Djokovic against No. 4 Dominic Thiem.
The guys ranked 1-4 hadn't been the last quartet at any tour event since the 2012 Australian Open, a span of nearly 500 tournaments. It's quite a contrast to the women's semifinals Friday, with only one player ranked in the WTA's top 25: That's No. 8 Ash Barty, who faces 17-year-old American Amanda Anisimova, while Johanna Konta plays Czech teen Marketa Vondrousova. None has ever reached a major final.
Federer, meanwhile, owns a men's-record 20 major championships. Nadal is next with 17, including 11 at the French Open. Djokovic is third on the list with 15. Each has completed a career Grand Slam, too.
"The three greatest players that ever played the game, probably," said Alexander Zverev, who went up a break against Djokovic and served for the first set in their quarterfinal Thursday before falling apart in what became a 7-5, 6-2, 6-2 loss to a man who is eyeing a fourth Slam title in a row.
"Rafa is someone that on clay is probably the toughest to beat out of everybody," the fifth-seeded Zverev continued. "Novak, once he gets up on you, he doesn't let go. ... Roger has so many different kind of things and has a lot of variety. He always has a way to get back in a match."
One of these semifinalists is not like the others: Thiem.
The 25-year-old Austrian has yet to win a major tournament, although he was the 2018 runner-up to Nadal in Paris and reached his fourth semifinal in four years at Roland Garros by eliminating No. 10 Karen Khachanov 6-2, 6-4, 6-2 Thursday.
"I know now how tough it is to get here, to get that deep in a tournament. And, I mean, these three, they are doing it (for), I don't know, 10, 15 years, almost at any Grand Slam. So that shows what their level is," Thiem said. "They are absolutely amazing. But on the other hand, I know all three of them. I have played many, many times against all of them. I feel really good in their company. But I'm trying everything to beat them."
Unless Thiem can defeat two of the other men left, this will be the 10th straight Grand Slam trophy that ends up in the hands of Federer, Nadal or Djokovic, who is 32.
"We're a bit older," Djokovic said, "but we have still been enjoying some of our best tennis in (the) biggest events."
He has won all 15 sets he's played over the past two weeks. Federer and Nadal dropped only one set apiece so far.
As well as Federer has played in his first French Open since 2015 — varying his return stance, knowing when to pick his spots to charge the net — nothing compares to the challenge of taking on Nadal on red clay.
Everyone knows that. Nadal is 91-2 at Roland Garros for his career, 5-0 against Federer. Nadal leads their overall head-to-head 23-15, including 13-2 on clay and 9-3 at majors. Federer has won the last five matches, all on hard courts.
Can Federer's one-handed righty backhand withstand the barrage of Nadal's topspin-laden lefty forehands that usually make the difference when they meet in Paris?
Can Nadal continue his recent resurgence after entering May without a title for the first time since 2004?
The only time Federer won the French Open, in 2009, he didn't need to get through Nadal.
This time, he must.
Both will be well-rested: Their quarterfinals were Tuesday.
"Like against any player, there is always a chance. Otherwise nobody will be in the stadium to watch, because everybody already knows the result in advance," Federer said. "You just never know. He might have a problem. He might be sick. You never know. You might be playing great or for some reason he's struggling. Maybe there's incredible wind, rain, 10 rain delays. You just don't know."