TENNIS/French Open: Nicole Vaidisova, possibly the oldest-looking 17-year-old in Grand Slam history, has already won the youth-against-experience battle twice to get to the French Open semi-finals. The humiliation of Amelie Mauresmo and the defeat of Venus Williams added up to as much experience as any teenager could hope to greet and beat in one week. This has definitely not been a tournament for the old stagers.

The young Czech, who learned to hit her ferocious ground strokes and serves in the "No Tomorrow" school, now meets the relatively elderly Russian Svetlana Kuznetsova (20) for a place in the final, while the positively ancient 22-year-old and 23-year-old Belgians Kim Clijsters and Justin-Henin Hardenne will bring a certain familiarity to bear on the other side of the draw.

Henin-Hardenne is hoping to win her third title here while Clijsters, who could be said to be in better form, seeks to win the title for the first time, having lost in two finals.

There is another motivation for Clijsters, although only secondary to becoming champion. If she wins the match against an opponent she has been meeting since the two were beating their way around the kindergarten circuit, she will become the first player in professional tennis history to rise from outside the top 100 to number one within a year.

Clijsters first reached number one in August 2003, missed most of 2004 because of a left wrist injury that ultimately required surgery, then made a phenomenal comeback in 2005 consisting of nine tour singles titles, including her first major, the US Open.

"I am certain that Kim told you that I would be the favourite on paper," said Henin-Hardenne. "I think it will be 50-50. But this is what we all do. She says clay isn't her favourite tournament and she was here in the final twice. I don't believe this. That's not a problem," she added before engaging in some of her own prematch propaganda.

"I'm not completely at the top these days," she complained. "Since my problems in January, I've remained somewhat fragile. I'm taking medication to try to feel better and try and be able to rest better."

There has been a lot of talk this year from players in their early and mid-20s, who complain they cannot recover as quickly as the teenagers. Henin-Hardenne, Clijsters and Martina Hingis have had to accept that playing so intensely from an early age does have consequences.

"It's true," said Clijsters. "A tennis career is not like a usual job. It's a short career. The Williamses made us train harder, become more powerful, move better. After a while it takes it out on your body."

No such whimpering from the more robust Vaidisova or Kuznetsova, although, in her win over Dinara Safina in the last round, Kuznetsova admitted to an onslaught of nerves that had her paralysed in the first set. If that happened in the quarter-finals, the semi-final stage is unlikely to be less stressful. All set then for a Clijsters final against the kid who's too young to buy a beer.