Maria Sharapova is 20, the same age as Andy Murray, Novak Djokovic and Ana Ivanovic, two years younger than Jo-Wilfried Tsonga and five years the junior of Justine Henin, the stand-out player in women’s tennis whose game and confidence Sharapova tore asunder in the biggest drubbing of a No 1 seed in a grand-slam tournament for nine years.

Yet another remarkable day at the Australian Open was brought to a dewy-eyed close as Tsonga, the Frenchman who eliminated Murray in the first round, collapsed face down after beating Mikhail Youzhny in straight sets and celebrated reaching the semi-finals of this level of championship for the first time. A couple of hours earlier, sheer radiance had beamed from Sharapova, who has reached this stage ten times already.

When you consider her relative youth and that, between them, Henin, Amélie Mauresmo and Serena and Venus Williams had been to nine semi-finals by the same age, you begin to appreciate what the Russian has achieved, in addition to her two grand-slam victories – the US Open triumph in 2006 being a considerable follow-up to her breakthrough at Wimbledon two years previously.

Against Henin she was breathtaking in winning 6-4, 6-0. Even those who had viewed her as a devil-may-care 12-year-old had never seen her play this well. Her Wimbledon final performance of 2004 against Serena Williams was that of a 17-year-old displaying consummate poise, but this was different.

This was the Sharapova who was supposed to be searching for her game destroying the finest player of the present era. Wimbledon aside, Henin has won all there is with a security of purpose and a fabulous strategy that usually rendered opponents helpless.

Here, though, she faced a player who did not contemplate defeat and refused to take a backward step. Not since Jelena Dokic, of Yugoslavia at the time, beat Martina Hingis for the loss of two games in the first round of Wimbledon in 1999 has a No 1 seed been so emphatically humbled in a grand-slam event. Not only that, but Henin, the Belgian, was on the crest of a 32-match winning streak. What a way for anyone of such pedigree to come crashing down.

But Sharapova was wonderful. There was not a facet of her game that was not razor sharp, right from the start. One lost count of the number of times she picked off Henin from the back of the court, especially on the cross-court backhand. There was an edge to her serve and an astonishing level of control from the ground; all of which, mercifully, was delivered with a minimum of noise.

“The stars were shining tonight,” she said. “It was just meant to be. I was supposed to hit three slices in a match, I was supposed to come in exactly nine times and drop-shot two and hit four lobs – that was the plan [her tongue was in cheek here].

“But I was taking care of my side of the net. I was worried about what I had to do. I wasn’t worried about what she was doing or what she was going to do. What I mean by that is that I was in control of my game. I was just concentrating on what I had to do throughout the match and even though I had a little letdown, I still kept going, fighting, and I was trying to get every single ball out there. I came in really prepared to play a three to four-hour match. I was ready for it, mentally and physically.”

Not only was the No 1 seed ousted, but the defending champion, too. Serena Williams had not a single excuse for her stunning 6-3, 6-4 reverse to Jelena Jankovic as the Serbian avenged last year’s fourth-round defeat by Williams here. How well Jankovic played, but how inexplicably woeful was Williams.

In the first men’s semi-final, Rafael Nadal, the world No 2 from Spain, who was written off by many before the tournament, will play the ebullient Tsonga. Having been the unseeded Frenchman’s first victim here, how must Murray be feeling today as he sets off in the rain for another training session in the relative desolation of Roehampton, southwest London?

Maria’s milestones

March 2002, Indian Wells, California At 14 years and 10 months, Sharapova made her debut on the Sony Ericsson WTA Tour seven years after arriving in the US almost penniless from Siberia. She beat Brie Rippner, of the US, 5-7, 6-1, 6-2 at the Pacific Life Open to announce herself on the world stage.

July 2004, Wimbledon At 17 years and 2 months, she became the third youngest women’s champion when she beat Serena Williams, the No 1 seed, 6-1, 6-4 in gloriously uninhibited fashion. She called Yelena, her mother, on her mobile phone from Centre Court. An iconic moment.

September 2006, US Open Wearing a stunning all-black outfit in the form of a cocktail dress inspired by the film Breakfast at Tiffany’s, Sharapova beat Justine Henin 6-4, 6-4 to win the title.