Now they'll go head to head.
Both advanced to Friday's semifinals with victories in straight sets, finishing less than 10 minutes apart. Nadal drubbed Stanislas Wawrinka 6-2, 6-3, 6-1, and shortly thereafter Djokovic eliminated 35-year-old Tommy Haas 6-3, 7-6 (5), 7-5.
So much for the preliminaries to set up a much-anticipated rematch of last year's final, which Nadal won for a record seventh French Open title. He's 57-1 at Roland Garros and bidding to become first man to win eight titles at the same Grand Slam event.
"I'm ready to play five sets," Djokovic said.
The Serb, ranked No. 1 and the winner of six Grand Slam titles, seeks the only major championship he has yet to win. With two more victories he would become the eighth man to complete a career Grand Slam.
"I would prefer an easier opponent," Nadal said. "But it's Novak, and I have to accept that it's going to be a very tough match."
The other semifinal pits Spaniard David Ferrer against Jo-Wilfried Tsonga, who's trying to become the first Frenchman in 30 years to win Roland Garros.
Advancing on the women's side were defending champion Maria Sharapova and two-time Australian Open winner Victoria Azarenka, and they'll meet Thursday. The other semifinal will match No. 1 Serena Williams against 2012 runner-up Sara Errani.
Nadal leads Djokovic 19-15 but lost their most recent meeting in the Monte Carlo final on clay in April. Nadal leads 6-3 in Grand Slam meetings.
"I played a great match when I faced him on clay this year at Monte Carlo," Djokovic said. "That match gave me a bit of confidence against him. But here in Roland Garros, he's very good. He has lost only once in the past 10 years. It will be very difficult for me. But I'm in a very good position now."
Because Nadal's ranking slipped during a seven-month layoff because of a knee injury, he and Djokovic wound up in the same half of the draw. As a result, they'll meet before the final at a major event for the first time since 2008.
Both were near top form in the quarterfinals.
Djokovic reached his 12th consecutive Grand Slam semifinal and improved to 33-4 this year by wearing down Haas, the oldest French Open men's quarterfinalist since 1971. Djokovic built an early lead, winning 40 of his first 43 service points.
Haas found himself on the verge of pulling even at 5-all in the tiebreaker, but Djokovic smacked a backhand winner to end a 24-stroke rally -- longest of the match -- and won the next point as well for a two-set lead.
He wobbled at the finish, but Haas was too tired to put up much of a fight. Djokovic kissed the line with a backhand winner on match point, and after the handshake ritual at the net, let out a scream and threw a punch, ready for Rafa.
Nadal, seeded No. 3, turned in his finest performance of the tournament yet. After dropping the first set in each of the first two rounds, he has won 12 sets in a row.
"I had a difficult first week," he said. "The last two matches were much more positive. I played today at a very good level."
Nadal improved to 10-0 against Wawrinka and has won all 22 sets they've played.
Sharapova needed a comeback unlike any other in her career to reach the semifinals, rallying past Jelena Jankovic, 0-6, 6-4, 6-3. It was Sharapova's first win after losing an opening set 6-0.
The No. 2-seeded Sharapova earned her first French Open title a year ago to complete a career Grand Slam. She has won 12 matches in a row at Roland Garros, where her 42-9 record is the best among active women.
"Obviously it only gets tougher from here," Sharapova said, "but I'm really happy I'm at this stage again."
She's 5-7 against No. 3 Azarenka, who reached her first Roland Garros semifinal by beating Maria Kirilenko 7-6 (3), 6-2.
The warmest weather of the tournament greeted the last of the quarterfinalists, and Jankovic quickly had Sharapova sweating. In the first set the Russian repeatedly missed the lines by narrow margins or clipped the net cord, and the match was 35 minutes old before she won a game -- and only then because Jankovic double-faulted on break point.
Jankovic won 27 points in the first set, 20 on unforced errors by her opponent.
"I still felt like I was in the match," Sharapova said. "And I was."
She then began to find her range while hitting even harder than before, while Jankovic did her best to withstand the barrage. In contrast to Sharapova's metronomic shrieking, Jankovic went about her business in silence -- until she started muttering to herself as her lead disappeared.
"It was a big fight," Jankovic said. "It was great tennis out there. We battled."
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