Clijsters has her eye on the ball again after sabbatical

Belgium's Kim Clijsters in action against Belarus' Victoria Azarenka in the second round of the Rogers Cup in Toronto in August.

Two appetising extra ingredients will be adding greater flavour to this year's women's singles. Kim Clijsters and Maria Sharapova, champions in 2005 and 2006 respectively, are both aiming to make up for lost time after their respective voluntary and enforced absence from the WTA Tour. Both former world No 1s have shown during their recent comebacks that they still possess the talents to embarrass those who have followed them up the world rankings ladder. The return of Clijsters has been marginally the more impressive.

The charming Belgian decided two years ago that domestic bliss of marriage and motherhood should replace the relentless desire to make improvements to her forehands and backhand. An invitation to play an exhibition match on Wimbledon's hallowed Centre Court in the spring, however, relit her fire and proved the catalyst for a determined resumption of full-time business. Unseeded Clijsters is regarded as one of the most dangerous floaters in a quarter of the draw occupied by world No 3 Venus Williams.

Clijsters, still only 26, may not yet have regained sufficient sharpness to derail the two-time Flushing Meadows champion in a possible fourth-round encounter but her form in the early stages of what she describes as her "second career" suggests an upset is not out of the question. Four of the world's top 20, notably French Open champion Svetlana Kuznetsova, another former queen of New York, perished at the skilful hands of Clijsters in her first two comeback events and others are surely destined to follow.

Prevented from defending her only grand slam title here three years ago by a wrist injury, Clijsters is raring to go in one of her happier hunting grounds. "I think the amount of time that I put into my tennis is shorter now, but the quality is a lot higher,'' represented an ominous warning to her rivals. Sharapova, still a slip of a lass at 22, has been drawn uncomfortably close to fellow Russian Elena Dementieva who goes into this tournament as confident as any having recently avenged a narrow Wimbledon semi-final defeat by Serena Williams, the defending champion here.

The reluctance of Sharapova to put too much strain on her recovering shoulder may put a third-round conquest of world No 4 Dementieva beyond her but if she gets over that daunting hurdle, she could do as much damage in the top half of the draw as Clijsters is likely to do in the bottom half. Serena, not for the first time, believes this is a grand slam that is hers for the taking. If she wins it she will hold three of the four major titles and inflict further misery on Dinara Safina, the Russian who holds the world No 1 ranking without having won a slam.

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