MELBOURNE, Australia (AP) -- The intensity was vintage Rafael Nadal.
On the stroke of midnight, he thrust his arms up and punched the air, sealing the victory that sets up the most anticipated semifinal at the Australian Open in quite some time.
Roger Federer did his part to put this in place. In the previous match on Rod Laver Arena, he beat 2009 U.S. Open champion Juan Martin del Potro 6-4, 6-3, 6-2 in a quarterfinal marking his 1,000th tour-level match.
A Federer-Nadal semifinal had been looming since the draw for the season's first major - the first time the pair have been in the same half at a Grand Slam tournament since 2005.
Playing with a new racket and a heavily taped right knee, Nadal was at his demonstrative best, rallying after losing the first set to beat Tomas Berdych 6-7 (5), 7-6 (6), 6-4, 6-3.
Yelling "Vamos," disputing line calls, pumping his arms after winning big points and bounding around like a hyperactive kid, Nadal ripped winner after winner against Berdych in a 4-hour, 16-minute display of pure intimidation.
He said he was nervous in the first set - he'd lost in the quarterfinals two straight years - but by the third and fourth sets things had indeed changed.
"The character on court, the way to win the points ... the level is very positive, much, much better than the end of the season," he said. "Semifinals is fantastic result for me."
Federer finished his match with one of his classic, one-handed backhands against Del Potro, one of only two men who have beaten him in a major final. The other is Nadal, who has done it six times.
That lopsided record aside, there's a touch of extra tension this time in this usually cordial rivalry. Nadal had told Spanish reporters during a discussion about player discontent that Federer liked to protect his reputation as a gentleman by saying nothing negative in public and letting others "burn."
Both have since played down the comments. On Tuesday, Federer said it didn't damage their relationship.
"No. No. Honestly, no," he said. "It was here for one day and then gone again. I'm happy about that because it didn't deserve more attention than it did. So for me, it's another great match with Rafa. ... Obviously I'd like to play Rafa because of our great epic match earlier in the finals here a few years ago."
Thursday's match will be the first time they have met at Melbourne Park since Nadal won the 2009 title in five seesawing sets. Nadal collected the trophy from the great Rod Laver after consoling Federer as he sobbed in the background.
"We are talking about a player who has won 16 Grand Slams, and I've won 10," Nadal said. "We have played a lot of matches together, many in very important moments for our careers. So the matches against him are always special, even if we are (ranked) 20 against 25."
One of the women's semifinals is already set up, with defending champion Kim Clijsters showing too much experience in a 6-3, 7-6 (4) win over Caroline Wozniacki, who remains without a major title and will now lose her No. 1 ranking.
Clijsters has a left ankle sprain that requires almost constant treatment, but expects to be fit for the next match against third-seeded Victoria Azarenka, one of the three women who can finish the tournament with the top ranking.
The two others - Wimbledon champion Petra Kvitova and Maria Sharapova - are in action Wednesday. Kvitova opens play at Rod Laver Arena against Sara Errani of Italy, followed by Sharapova against Ekaterina Makarova in an all-Russian match. No. 56-ranked Makarova is coming off a straight-set win over five-time Australian champion Serena Williams.
Defending men's champion Novak Djokovic has an evening match against No. 5 David Ferrer, who beat Nadal in the quarterfinals last year. Djokovic overtook Nadal and Federer for the No. 1 ranking last year by winning three of the four majors, starting with an Australian Open final win over Andy Murray. Murray takes on No. 24 Kei Nishikori of Japan on Wednesday.
Given the dominance last season of the top four, a Djokovic vs. Murray semifinal seems most likely. In 2009, the competition was considered more of a two-man race.
Federer was aiming to equal Pete Sampras' record of 14 Grand Slam titles and was confident despite entering the Australian Open with the No. 2 ranking.
Nadal had fended off Fernando Verdasco in 5-hour, 14-minute late night semifinal - the longest match at the Australian Open - and said he could barely walk, let alone practice the following day. He'd also had a day less to prepare for the final than Federer did. Still, he became the first Spaniard to win the Australian title.
Nadal has won 17 of their 26 head-to-head matches overall, including a 7-2 lead in Grand Slam matches. Federer won the last meeting, a 6-3, 6-0 demolition at the season-ending championship in November.
It has been almost seven years since the pair last met in the semifinals of a major.
"Yeah, it's been a long time - I don't know when the last time has been when we played in the semis of a slam," said Federer, who is usually an extremely reliable statistician. "Maybe back in 2005, maybe at the French potentially, I don't know."
For the record: Nadal won in four sets against the then No. 1-ranked Federer en route to the title at Roland Garros.
"We have been on opposite sides of the draw many times," Federer said. "I guess it's a nice changeup. OK, it doesn't allow a rematch for the Australian Open final here, you know, but I think it's good for tennis that it changes up a bit."
Nadal certainly didn't want to miss another chance at Federer. He didn't finish last year in good form and has already talked about taking time off next month to rest a sore shoulder. He hurt his knee by sitting in a chair at his hotel on the eve of his first-round match.
Nadal saved four set points in the first set against Berdych, including one with a stunning passing shot on the 29th point of a rally. But the seventh-seeded Czech persevered and won the ensuing tiebreaker.
During the tiebreaker, a shot by Berdych shot landed out and Nadal returned it, then challenged. Chair umpire Carlos Bernardes wouldn't allow it because Nadal hadn't immediately stopped play, but Nadal responded by saying he didn't challenge immediately because he thought the linesman had called it out. The replay showed the ball out and Nadal thought the umpire should have overruled.
He didn't win another point in the tiebreaker. In the second set, as Nadal lined up to serve in a key point, a man called out from the crowd: "Come on Rafa, we want a Roger-Rafa semifinal Thursday night."
Nadal obliged. Improving as he went along, Nadal hit consecutive down-the-line forehands to break Berdych early in the fourth set. Berdych did well to hold in the fifth game, which lasted 13 1/2 minutes, but Nadal dominated from there and sealed the match with a service break as the clock struck 12.
"I started moving a little bit inside the court after I went 20 meters behind the baseline, just trying to find solution," Nadal said. "At the end of the match I finished it returning fantastic."
