Tennis/ US Open: To date the image and earnings of Maria Sharapova have by far outshone her achievements. Last year the US-based Russian, whose only slam title came at Wimbledon two years ago, made £13.4 million, of which all but a million was from endorsements. In comparison Roger Federer, the winner of eight grand slams, earned £11.7 million.

The 19-year-old Sharapova has been promoted more heavily than anybody else here, her Nike television commercial showing her striding through the Waldorf to Flushing Meadows to the tune of I Feel Pretty from West Side Story.

Today is the time for the music to stop and for her to break the semi-final hoodoo she has suffered since that Wimbledon victory.

She lost to Amelie Mauresmo on grass this summer, her fifth semi-final defeat in the last seven slams, and it is the French world number one and reigning Australian and Wimbledon champion whom she plays again today, having not previously beaten her in three attempts.

"I thought I had all the momentum in the third set at Wimbledon this year, but I didn't use it to my advantage," she said.

When Sharapova, who left Russia when she was nine, beat Serena Williams in the 2004 Wimbledon final it appeared this might be the start of her domination of the sport. Yet since then, despite her ferocious intensity, the other leading players have exploited a seemingly inherent brittleness. Sharapova claims it is a question of experience and ill luck with injuries.

"The last thing I worry about when I go on court is trying to prove anything to anyone," she said after beating France's own Russian-born teenager Tatiana Golovin 7-6, 7-6 in the quarter-finals.

The second semi-final is between Justine Henin-Hardenne, the winner of five slam titles and reigning French Open champion, against Jelena Jankovic, the surprise package of this year's US Open, having beaten three seeds to date, including Svetlana Kuznetsova, the 2004 champion.

Henin has appeared in all three slam finals this year, losing to Mauresmo in Australia by default and at Wimbledon, and beating Kuznetsova at Roland Garros.

Jankovic was an outstanding junior who until this tournament had not sparked at a slam, although she knocked out Venus Williams, the reigning champion, in the third round of this year's Wimbledon.

Rafael Nadal's quarter-final defeat by the unseeded Mikhail Youzhny did not create the waves it would have done in Europe, simply because the Americans have yet to see the best of the world number two. Youzhny will play the 2003 champion Andy Roddick in tomorrow's semi-finals.

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