Random as Grand Slam tournament draws are meant to be, Novak Djokovic and Roger Federer keep bumping into each other in major semifinals, and it could happen again at Wimbledon.

The No. 1-seeded Djokovic, the defending champion, and No. 3 Federer — a six-time winner at the All England Club — were placed in the same half of this year's field Friday. They've played in the semifinals at five of the past seven Grand Slam tournaments, with Djokovic holding a 4-1 edge, including a victory two weeks ago at the French Open.

Similarly, No. 2 Rafael Nadal and No. 4 Andy Murray are making a habit of major semifinal meetings: Wimbledon could make the fifth time in nine majors they've played at that stage. Nadal is 4-0 against Murray in that stretch, including at the All England Club in 2010 and 2011.

The potential men's quarterfinals at Wimbledon, where play begins Monday, include Djokovic vs. No. 6 Tomas Berdych, the 2010 runner-up; Federer vs. No. 8 Janko Tipsarevic or No. 11 John Isner, the big-serving, 6-foot-9 American best known for beating Nicolas Mahut 70-68 in the fifth set of the longest match in tennis history; two-time champion Nadal vs. No. 5 Jo-Wilfried Tsonga; and Murray vs. No. 7 David Ferrer or No. 9 Juan Martin del Potro.

Isner, it so happens, could wind up with a second-round match against Mahut — an annual occurrence at the grass-court Grand Slam tournament. After their 11-plus-hour marathon in the first round in 2010, they met again in the first round last year.

The women's quarterfinals set up by Friday's draw are No. 1 Maria Sharapova vs. No. 8 Angelique Kerber; No. 6 Serena Williams, a four-time champion, vs. Petra Kvitova, the defending champion; No. 3 Agnieszka Radwanska or Venus Williams vs. No. 5 Sam Stosur; and No. 2 Victoria Azarenka vs. No. 7 Caroline Wozniacki.

Sharapova and four-time Wimbledon champion Serena Williams could meet only in the final — which would be a rematch of 2004, when Sharapova won her first major title.

Coming off a French Open championship that completed a career Grand Slam, Sharapova managed to avoid plenty of top players who wound up on the other half of the bracket, including Kvitova, Wozniacki, Julia Goerges, Ana Ivanovic and Marion Bartoli.

Sharapova's toughest early test might come in the second round against 40th-ranked Tsvetana Pironkova of Bulgaria, who upset Venus Williams en route to the semifinals at Wimbledon in 2010, then got to the quarterfinals last year.

Venus Williams, unseeded at Wimbledon for the first time since she made her tournament debut at age 17 in 1997, could face Radwanska in the second round — a rematch of their second-round meeting at the French Open, won by Radwanska.

Kim Clijsters, also unseeded this year after missing three months with injuries, was drawn to face another former No. 1, Jelena Jankovic, in the first round. Clijsters withdrew from a tuneup event in the Netherlands on Friday because of a stomach muscle strain, but vowed to be at Wimbledon for what she says will be the last time; she announced she'll retire after the U.S. Open in September.

Djokovic, whose 27-match Grand Slam winning streak was snapped by Nadal in the French Open final, will try to begin a new run when he faces former No. 1 Juan Carlos Ferrero on Monday's first match at Centre Court. Ferrero, the 2003 French Open champion, has talked about the possibility of retiring after this season.

Djokovic then could face Ryan Harrison of the U.S. in the second round.

Among the intriguing first-round encounters are Tsonga against 2002 Wimbledon champion Lleyton Hewitt, who needed a wild card to get into the draw after his ranking dipped below 200; 20th-seeded Bernard Tomic, who reached the quarterfinals as an 18-year-old qualifier last year, against David Goffin, a baby-faced 21-year-old who took a set off Federer in the French Open's fourth round this month; and Tipsarevic against 2002 runner-up David Nalbandian, who was disqualified from the final at the Queen's Club warmup event last weekend after kicking an advertising board and injuring a line judge.

Murray, still seeking to become the first British man since 1936 to win a Grand Slam title, faces a tricky path that starts with former top-five player Nikolay Davydenko and could include 6-foot-10 Ivo Karlovic and the big serves of No. 16 Marin Cilic, No. 21 Milos Raonic or No. 32 Kevin Anderson.

Federer, owner of a record 16 Grand Slam titles and a record 237 Grand Slam match wins, has a first-round match against 43rd-ranked Albert Ramos of Spain, a guy making his Wimbledon debut and with a career record of 1-4 at major tournaments.


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