"The rivalry they've had has been wonderful, first for the game, and for players including myself who love the game," said Guy Forget, the French Davis Cup captain. "We look at the match not only from an emotional point of view but also from the standpoint of physical ability, strategy, the technical part.
"It's great to see always what these guys are trying to do to beat each other. I can't wait."
Federer wanted the matchup, too.
"I'd obviously like to play Rafa because of our great, epic match earlier in the finals here a few years ago," Federer said. "I'd like to get a chance to play him here again."
That was Federer after comfortably dispatching Juan Martin del Potro 6-4, 6-3, 6-2 on Tuesday afternoon. Tomas Berdych almost deprived us of the dream tussle, but in the end, Nadal won their nightcap in four thrilling sets and more than four hours, 6-7 (5), 7-6 (6), 6-4, 6-3.
"We played a lot of matches against each other, in very important moments for our careers and very high moments," Nadal said afterwards. "So the match is special."
When the season's opening major began, though, there were questions surrounding both men.
Would Federer, the 16-time Grand Slam winner, and Nadal, who owns 10 majors, even get this far?
Nadal suffered from a sore shoulder and had to adjust to a heavier racket. He then injured his knee in bizarre fashion -- while sitting down. He said he's taking all of February off to recharge. Federer, meanwhile, was nursing a tender back, which, unusually, forced the 30-year-old to bail mid-tournament in Doha.
But Federer has looked sharp, not dropping a set. In a contest that figured to be tricky, he sizzled against del Potro, flashing his versatile repertoire against the befuddled Argentine.
"I'm really happy with my game," Federer said in the wake of his 1,000th match. "I'm moving well; I'm serving well; I'm hitting the ball clean."
Nadal cruised into the quarterfinals. He subsequently had to dig deep to edge a dogged Berdych, who customarily had his small fan club courtside. Nadal didn't flash a versatile game. Rather, he competed hard, wore his opponent down -- nothing new -- and benefited from a costly miss by Berdych in the second-set tiebreaker.
His level, however, rose substantially in the third and fourth sets.
"The fourth set was one of my best levels on this kind of surface," Nadal said.
"And I think their semifinal is going to be played at a high level also," said Dirk Hordorff, who coaches several players on the tour.
Federer, for all his momentum, has serious numbers to overcome in his 27th meeting with his younger, brawnier rival, and not simply his desultory 9-17 head-to-head record.
The Swiss last downed Nadal at a Grand Slam five years ago at Wimbledon. Since then, Nadal is 4-0 in the best-of-five set format.
"You know if it lasts a long time, Rafa is such a fighter and he's so good in defense, that it wears you out, whether it's physically or mentally," Forget said. "It's very hard to beat him when you are feeling fatigue after three hours of playing. Normally you're not as sharp, sometimes your attacks don't come at the right time, and he takes advantage of that."
Nadal handed Federer two of his toughest losses, triumphing in arguably the greatest match of all time at Wimbledon in 2008 and repeating his five-set heroics at the ensuing Australian Open. Few thought Nadal had it in him in 2009, given he had contested a five-hour, 14 minute marathon against Fernando Verdasco in the semifinals two days before. Federer enjoyed an extra day of rest back then.
"I hope [Wednesday] I will be able to practice with normal conditions," Nadal said. "But I will be able to practice. In 2009, the day after, I wasn't able to practice. That's important."
With legendary Aussie Rod Laver in attendance, a devastated Federer memorably broke down during the trophy presentation; Laver, incidentally, is expected to be in the stands Thursday night. A victory for Nadal would be another blow to Federer.
Federer will surely be dwelling on the pair's previous tilt in London in November, not pondering any potential loss. All parts of Federer's game were firing, and he thrashed Nadal 6-3, 6-0 in an hour at the year-end championships. Further, Federer hasn't lost a match since the U.S. Open.
"Roger has been playing so well since the end of last season, and it seems like he's still on a roll," Forget said. "I think he'll try to impose his game and speed so he doesn't get into those long rallies. You know when you play Nadal that you have to be really sharp from the beginning of the match so you get him into a mode where he feels like he's always behind."
Nadal, surprisingly, publicly criticized his friend prior to the event. Federer said he's already forgotten about it.
Judging by their past meetings in Grand Slams, Thursday's duel could linger in the memory.
Prediction: Nadal in five.
London-based Ravi Ubha covers soccer and tennis for ESPN.com. You can follow him on Twitter.