Mid-level players pose a bigger threat than ever to the big names of tennis

As the Dubai Duty Free Championships continue, rising levels of fitness make the top players ever more vulnerable in the cut-throat world of women's tennis.

Odd, but while the foremost attraction last night at the Dubai Duty Free Tennis Championships clearly would have been the No 2-ranked and No 1-seeded Caroline Wozniacki, the less-recognised woman across the net might instruct us more about the essence of the sport circa 2011.

Perhaps only a person without enough hobbies - oh, hello - could recall that in 2007, Anna Chakvetadze ascended to the US Open semi-finals, the French and Australian quarter-finals and a pretty celestial No 5 in the world.

By last night barely more than three years thence, when a gastrointestinal illness caused her to retire amid a heady second set, Chakvetadze held down No 51. That almost certainly says less about her than it does about the rest.

The top of the game might have gone shorn of some might lately, but the middle can beat you like never before, and while the power has quashed the variety in styles, the whole tour is capable of blowing a groundstroke past your ear and showing you the way home in the first round.

"I read an interview with Maria Sharapova, and she said the tennis is different now," said Svetlana Kuznetsova, the 25-year-old winner of two grand slams and a finalist in two more. "I agree. For example, before it was top 10 and the rest. It was like you go to play tournaments, first one, two, three rounds, it was like you go easy. Now it's not like this anymore."

Kuznetsova spoke not of the top 10, which in recent years has lost Justine Henin twice, Sharapova to injury often and, lately, Serena Williams to long-term injury. She spoke of the mauling middle.

"I'm saying other girls, they're very even and you don't have such easy matches first rounds. I don't say about the top. This is the other discussion. To have two or three players more in the draw, like Venus, Serena, it doesn't make big change on the first rounds because you don't face them [anyway] the first rounds. I'm saying about girls like Pironkova …"

She meant Tvetsana Pironkova, the Bulgarian player Kuznetsova outlasted yesterday by 7-5, 2-6, 6-4.

Only two players from the top 10 of this week in 2008 - Venus Williams and Jelena Jankovic - remain. Beyond the then-No 1 Henin's retirement, just as telling would be the ones whose confidence frayed in the upgraded duress from the middle.

Ana Ivanovic, No 2 then, stands No 19, and had to climb to reach that. Daniela Hantuchova, No 7 then, holds No 29. Marion Bartoli has done well in the maelstrom to sit at No 17. Then No 3 Kuznetsova lost confidence and found No 23.

Young names that pop up there and cause clatter - Chakvetadze, Nicole Vaidisova, Dominika Cibulkova, et al - have less chance than ever of staying there, or of pushing further once around the top-10 cusp.

"I see it this way," Kuznetsova said. "There are players who go up. They have no pressure. It comes, and maybe they have a little luck in the draw … They win one match, they get confident. They start to be confident, confident, and end up playing good and maybe top 10.

"And the next year, when you don't have as much confidence, you have to defend what you've done last year [in the 12-month points system]. Then you start to think, 'Oh, am I able to do that?' Or matches start to get complicated or every player knows how to play against you or each player that goes to play against you, they want to beat you more and more.

"Then you show how good you are, and if you're good enough to be in the top 10, to stay there."

That makes Jankovic's endurance more of a feat, as she and her guileful game have watched the tide pick up oomph rather literally.

"I don't know if I can say that maybe the first rounds are [harder]than before," she said. "But I can say that the girls nowadays are very fit and very strong physically. Everybody is working hard. Maybe five, seven years ago the emphasis was not so much on the physical part. It was more technical and girls kind of played tennis. Now it's becoming very, very powerful."

Then finally, as if that were not enough, older players catch on and catch up, so it becomes a world in which Kuznetsova can find herself today up against the enviable biceps of 30-year-old Francesca Schiavone, who amassed new found confidence when she hoisted the French Open trophy last June.

Suddenly, the two-time slam champion and four-time finalist sitting at No. 23 says of the one-time slam finalist and champion at No 4: "I have nothing to lose. She's the favourite. Pressure on her."