- After so much speculation about a possible Wimbledon final between Roger Federer and Rafael Nadal, 10 years after their last, tennis fans instead will get a semifinal featuring another outstanding rivalry: Nadal vs. Novak Djokovic.

Friday's showdown will be their 52nd meeting overall — the most for any pair of men and 14 more installments than Federer vs. Nadal — and first at the All England Club since 2011.

That was also the last time Nadal made it past the fourth round at the grass-court major; Djokovic, who holds a 26-25 head-to-head lead, beat him in that year's final.

"We always played in important stages, important places," said Nadal, who had a far rougher match in the quarterfinals than Djokovic, needing more than 4 hours to edge Juan Martin del Potro in a five-set thriller. "Friday is another important match against an opponent that is one of the most difficult ones that you can face. "

The first semifinal, between No. 8 seed Kevin Anderson of South Africa and No. 9 John Isner of the U.S., features two powerful servers with similar games who have a lot less star power and zero Grand Slam trophies while Nadal and Djokovic have combined for 29, including five at Wimbledon.

Anderson, 32, shockingly ended Federer's bid for a ninth championship at Wimbledon by beating him 13-11 in the fifth set of their quarterfinal Wednesday.

At least Anderson can boast of one runner-up finish at a Grand Slam, against Nadal at last year's U.S. Open.

"I'm trying to get to where he's already been," said Isner, 33, who has won all 95 of his service games this fortnight, thanks in part to a tournament-leading 161 aces.

Isner, who leads Anderson 8-3 in past meetings, is making his debut in the final four of a Grand Slam tournament.

Add in Nadal, 32, and Djokovic, 31, and it's the first time in the half-century of professional tennis that all four male semifinalists at any Grand Slam are in their 30s.