LONDON, UK - The only thing certain about this year's Wimbledon is that play won't be interrupted by rain - at least not on Centre Court. A few weeks ago Dinara Safina had the air of an increasingly dominant world No.1, with a Grand Slam title all that was needed to put any doubts to rest. But her loss to Svetlana Kuznetsova in the final at Roland Garros, and perhaps more worryingly, to Tamarine Tanasugarn on grass at 's-Hertogenbosch, have dinted her sense of invincibility. And there are plenty of other reasons why this year's Wimbledon field looks enticingly open.

Safina might be the top seed, but she has never been past the third round at this grandest of Slams, and what's more the Williams sisters are back - and for the first time in years actually seeded to reach at least the semis. Two-time Wimbledon champion Serena is the No.2 seed, while five-time and defending champion Venus is No.3. While numbers haven't really made a difference to them in the past, the sibling superstars will not have failed to notice they cannot meet before the final. Neither played a grass court tune-up, but that has never hurt their prospects before. They are sure-fire contenders regardless; Venus is in the same half of the draw as Safina.

Beyond that, the form guide gets a little murky, for upsets ruled the day at Birmingham, 's-Hertogenbosch and especially Eastbourne, where seven of the Top 10 were entered, yet only one of them made the quarterfinals.

Elena Dementieva, who finally broke through to the semis at the All England Club 12 months ago and is the No.4 seed this year, was the top seed at Eastbourne, but stumbled in the second round. After a great start to the year the Russian went off the boil, and underperformed on clay too.

Fifth seed Svetlana Kuznetsova knows how to adapt her game to grass and seemed to have momentum on her side after her triumph at Roland Garros, so her first round loss at Eastbourne - a tournament she won in 2004 - was a surprise. Likewise Jelena Jankovic, the world No.1 six months ago but now Wimbledon's No.6 seed, and Vera Zvonareva, the No.7 seed, fell early at the seaside resort. Zvonareva was making a return from ankle injury and might have struggled anyway Amélie Mauresmo, but Jankovic's loss to Anna Chakvetadze was a blow.

Changing of the Guard?

The indifferent form of some elite elite plays might just open the way for younger stars. Injury forced No.8 Victoria Azarenka out of Eastbourne, but she boasts the explosive power to cause trouble on grass. Fellow teen Caroline Wozniacki is seeded ninth, and arrives in London as the newly-minted Eastbourne champion, the fifth title of her young career. Having failed to defend her crown in Eastbourne, Poland's Agnieszka Radwanska, who is seeded 11th, will be keen to make amends.

Other seeds with Grand Slam or grass court credentials of note include Marion Bartoli, runner-up at Wimbledon in 2007 and a three-time semifinalist at Eastbourne; this year the Frenchwoman is seeded 12th. Ana Ivanovic, who slipped in the rankings after the French Open, is the No.13 seed while the player who beat her here last year and marched on to the semis, Zheng Jie, is the No.16 seed.

Mauresmo, the 2006 champion, is seeded 17th and clearly still capable of vintage displays, while French Open semifinalist Samantha Stosur could pose even more of a threat on grass as the No.18 seed. Despite her current ranking of No.59 Maria Sharapova, the 2004 champion, has been given a special seeding of No.24 on the back of her promising return from injury, which includes a quarterfinal run at Roland Garros and semifinal effort at Birmingham. Virginie Razzano, vanquisher of Dementieva, Radwanska and Bartoli on her way to the final at Eastbourne, is the No.25 seed.

Slovakia's Magdalena Rybarikova, who captured her first Tour title at Birmingham, is unseeded and plays Roberta Vinci of Italy in the first round. Thai veteran Tanasugarn, after her successful title defence at 's-Hertogenbosch, plays Spanish qualifier Arantxa Parra Santonja in the first round.

A wildcard have been awarded to Japanese veteran Kimiko Date Krumm, who lost to Steffi Graf in the semis here in 1996; the 38-year-old runs into Wozniacki in the first round. Other wildcard recipients include the American Alexa Glatch, Michelle Larcher de Brito of Portugal and Britons Elena Baltacha, Melanie South, Katie O'Brien, Georgie Stoop and Laura Robson, who won the junior girls' title last year and takes on Daniela Hantuchova in the first round on Monday.

British No.1 Anne Keothavong plays Austria's Patricia Mayr in the first round; No.32 seed Chakvetadze is a potential second round opponent for the Londoner.