MELBOURNE, Australia (AP) A lop-sided rivalry contested over more than a decade, and a newer but just as compelling one highlight the featured quarterfinals at the Australian Open on Tuesday.
Defending champion Serena Williams takes a 17-match winning streak into her last-eight encounter with Maria Sharapova that is a rematch of last year's final at Melbourne Park. Williams is 18-2 in their head-to-head encounters that began in 2004, and Sharapova hasn't beaten Williams since the WTA season-ending championships that year.
Top-seeded Novak Djokovic and No. 7 Kei Nishikori first played at the French Open in 2010, where Djokovic won in straight sets, and the Serbian player holds a 5-2 edge overall. Their only previous meeting at a Grand Slam came at the 2014 U.S. Open, where Nishikori won in four sets en route to the final.
Four-time champion Roger Federer plays Tomas Berdych in the other men's quarterfinal, while fourth-seeded Agnieszka Radwanska takes on No. 10 Carla Suarez Navarro in the second women's quarterfinal in the top half of the draw.
Here's a look at the matches:
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WILLIAMS VS. SHARAPOVA: The oldest woman to hold the No. 1 ranking - 34-year-old Williams - is also the most confident heading into yet another match with Sharapova. ''I just feel like I'm really confident in my game right now,'' Williams said, ''not against her or against any other opponent - I'm just really looking at me right now. And I feel like if I can just continue to play well, then it could be good.'' Good could be another Grand Slam singles title which would pull her level with Steffi Graf's 22. Sharapova is trying to play positive mind games to rid herself of that dreaded record of having not beaten Williams in such a long time. ''It's not like I think about, `What can I do worse?''' Sharapova said. ''I got myself into the quarterfinal of a Grand Slam. There is no reason I shouldn't be looking to improve and to getting my game in a better position than any previous round. It's only going to be tougher, especially against Serena.''
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DJOKOVIC VS. NISHIKORI: Djokovic had, by his lofty standards a shocking performance in his fourth-round match against Gilles Simon, making 100 unforced errors in a five-set win over a veteran who loves to keep the ball in play. ''Too many unforced errors today,'' Djokovic said after the match. ''I'm going to make sure that I decrease that number at least more than half and hope for the best. We've (he and Nishikori) played many times in the big tournaments.'' Asked to comment on Djokovic's strengths - before Djokovic's match against Simon - the Japanese player possibly jinxed his quarterfinal rival: ''I think the biggest thing is he doesn't miss. He doesn't give you easy points, any free points. I have to be the one to dictate.''
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FEDERER VS. BERDYCH: Federer is playing in his 12th Australian Open quarterfinal and holds a 15-6 edge over Berdych, although the Czech player beat Federer in four sets the last time they played in a Grand Slam in the 2012 U.S. Open quarterfinals. ''I think the court suits him (Berdych)... this sort of flatter bounce and faster court is good for his serves, good for his returns,'' Federer said of Rod Laver Arena, where the two have a day match scheduled. Berdych, who is playing his sixth consecutive quarterfinal here, says: ''I mean, it's Roger, so it's always going to be a huge challenge to play him. ''
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RADWANSKA VS. SUAREZ NAVARRO: Radwanska holds a 2-1 career edge over Suarez Navarro, although the Spanish player beat Radwanska in three sets the last time they met last year at the Miami Masters. When they last met at a Grand Slam - the second round of the 2012 U.S. Open - Radwanska won in three sets. It's been seven years since Suarez Navarro made a quarterfinal here. ''I know her style, you have to run a lot ...'' the Spanish player said. The winner of the match plays either Williams or Sharapova in the semifinals.
