MELBOURNE, Australia — Roger Federer is reluctant for now to talk about possibly playing Rafael Nadal in the Australian Open final, and with good reason.
    After all, he's playing Novak Djokovic.    Federer and Nadal have dominated the Grand Slam tennis, winning 21 of the last 23 titles. But Djokovic is dangerous, and Federer knows his one-match-at-a-time mantra is sound strategy.
    "He takes it to the opponent," Federer said.
    Federer routed Stanislas Wawrinka 6-1, 6-3, 6-3 Tuesday in the first all-Swiss quarterfinal at a major. Djokovic eliminated Wimbledon finalist Tomas Berdych 6-1, 7-6 (5), 6-1 in the night match.
    On the women's side, Caroline Wozniacki beat Francesca Schiavone 3-6, 6-3, 6-3 in one quarterfinal, and Li Na defeated Andrea Petkovic 6-2, 6-4 in the other.
    Nadal plays the night quarterfinal tonight against David Ferrer. He has an 11-3 lead in head-to-heads. A win could set up a semifinal against Andy Murray, the only man to beat Nadal in a major in 2010.
    Murray takes on Alexandr Dolgopolov, the breakthrough player of the tournament in today's other quarterfinal.
    Quarterfinals in the bottom half of the women's draw feature No. 2 Vera Zvonareva against No. 25 Petra Kvitova and No. 3 Kim Clijsters against Agnieszka Radwanska.

Wozniacki is already through to her first Australian Open semifinal and the top-ranked Dane will next meet Li, who made the semis last year. Li lost to eventual champion Serena Williams last year, and is growing in confidence.

Federer won the Australian crown by defeating Murray in straight sets in the final. Now he's aiming to be only the second man to win five Australian titles — Roy Emerson won six.

He lost the 2009 Australian final to Nadal, and didn't even make the championship match the previous year, when he entered the tournament as the two-time defending champ.

Federer was slowed by mononucleosis in 2008, and Djokovic capitalized.

"If I look back, I think Novak played another good match. He was very confident. He played a great tournament, which he also ended up winning," Federer said. "Both times he beat me, he played really well."

Federer has a 13-6 record against Djokovic and has won the last three since the U.S. Open. He has also won four of their six Grand Slam contests — but those two wins by Djokovic have been in big matches.

"He's a quality player who plays really offensive," Federer said.

After his victory over Berdych, Djokovic said he is still basking in Serbia's first Davis Cup title and it has given him extra confidence.

"Coming in here I was physically prepared, mentally motivated to make some success. So far it's been great," he said. "Today has been a real test, because he's No. 6 of the world and a very difficult opponent.

"I've played one of my best tennis in the last couple months. So I have nothing to lose playing Federer, who's the title defender here. We all know everything about him. I have to believe in myself in order to win that match."

Wozniacki showed plenty of belief, coming back from a set and a break down to defeat Schiavone, the French Open champion who is seeded sixth. Schiavone had reached the last eight after beating Svetlana Kuznetsova in three sets in 4 hours, 44 minutes, the longest Grand Slam women's singles match on record.

"Maybe in the third set I felt a little bit something physically, but it's not an excuse," Schiavone said. "I think I gave the best that I could do."

Wozniacki needed a medical timeout for painkillers and treatment on her left thigh after losing the first set. Her game improved after she removed the wrapping later in the second set.

Schiavone "started off really, really well and I didn't feel like I had the right timing," Wozniacki said. "So it was difficult for me in the beginning, but I fought back and I'm so happy that I'm standing here as the winner."

The match point was contentious — first called out by a line judge. An overrule by chair umpire Eva Aseraki forced Wozniacki to ask for a video ruling, which confirmed the initial call and ended the match.

Li, seeded No. 9, beat Petkovic to extend her winning streak to 10 matches after capturing the title in a Sydney tuneup tournament.

"I's good for me. I mean, the second time in the Grand Slam semifinal, always in the Australia Open, and also before I played well in Sydney," she said. "Hopefully I can do better in this year, and everyone will see me again."

No Chinese woman has won a major, but Petkovic says Li has what it takes.

"I think she played really well. I think she's going to win the tournament," the 30th-seeded German said. "She moves very well, she has a great footwork. She takes the ball very early. She plays flat and deep. She has this sneaky aggressive play, I would call it."