WIMBLEDON, England — Roger Federer could face No. 3-ranked Novak Djokovic in the semifinals en route to a bid for a sixth straight Wimbledon title.

Djokovic, the Australian Open champion, was drawn into Federer's half of the bracket Friday for the grass-court Grand Slam tournament that begins Monday.

Second-ranked Rafael Nadal, who lost to Federer in the past two finals, is in the other half of the draw. He could face two-time runner-up Andy Roddick in the semifinals.

In the women's draw, top-seeded Ana Ivanovic and two-time champion Serena Williams are in the same top half. No. 2 Jelena Jankovic and Venus Williams, the defending champion and four-time winner, are in the other half of the draw.

Federer, who has won 59 straight matches on grass, will open play on Centre Court on Monday against Dominik Hrbaty of Slovakia. Hrbaty, who reached a ranking of No. 12 in 2004, has dropped to No. 272.

Federer could face a third-round match against Gael Monfils, whom he beat in the French Open semifinals, and either 2002 champion Lleyton Hewitt — the last man to win Wimbledon before Federer— or Fernando Gonzalez in the fourth. His projected quarterfinal opponent is Spain's fifth-seeded David Ferrer.

Nadal, coming off his fourth straight French Open victory and first grass-court title at Queen's Club, will open against German qualifier Andreas Beck. Nadal could face Mikhail Youzhny in the fourth round, Britain's Andy Murray or 2007 semifinalist Richard Gasquet in the quarterfinals and either No. 4 Nikolay Davydekno or No. 6 Roddick in the semis.

Roddick has a possible fourth-round encounter against fellow American James Blake.

Djokovic, who lost to Nadal in the Queen's final, has a first-round match against Michael Berrer of Germany and could face a tough second-round matchup with Russia's Marat Safin, a former No. 1 and two-time Grand Slam winner. Djokovic could meet 2002 finalist David Nalbandian in the quarterfinals before a potential showdown with Federer.

The 21-year-old Serbian believes Federer is vulnerable after his lopsided defeat to Nadal in the French Open final and lack of a Grand Slam title this year.

"Some things are changing. I think he's a little bit shaken with that loss and mentally he has been struggling in the last couple of months," Djokovic said earlier this week in London. "New names are coming, fresh talented players who believe more they can win against him and I am one of them. Suddenly he is worried a little bit."

Venus Williams, seeded No. 7, will open defense of the women's title against British wild card entry Naomi Cavaday.

Williams could meet Sania Mirza in the third round, Daniela Hantuchova in the fourth, Jankovic in the quarters and 2004 champion Maria Sharapova in the semifinals.

The Williams sisters could meet in the final.

Ivanovic, who took over the No. 1 ranking after winning the French Open for her first major title, faces Rossana De Los Rio of Paraguay in the first round. She could face Anna Chakvetadze in the quarterfinals and either Serena Williams or No. 4 Svetlana Kuznetzova in the semis.

Serena Williams could face 2006 champion Amelie Mauresmo in the fourth round and either Kuznetsova or last year's runner-up, Marion Bartoli, in the quarters.