Britain's Tim Henman came off court after surviving a tense five-set fourth round match against Michel Kratochvil during the 2002 Championships and said his victory was due to the support of the crowd at No.1 Court.

"At two sets to one down and 2-1 down in the fourth, I was out of there. But somehow the good old crowd got me going again," he said. " I was really struggling with my movement and timing of the ball. I was very grateful for the massive help from the crowd. I could hear them in and outside the stadium.

"When the competition is this tight, I have a few influences that can help. The crowd [was] phenonomenal. It was pretty bizarre playing on the court when there was such a good atmosphere. You could sense and hear that there was an even better one outside on the hill. I just had to win, didn't I. Simple as that."

Each year Henman says much the same about the crowds who watch his games on Centre Court and No.1 Court and from the grassy hill behind No.1 Court that is always so packed with his supporters that is commonly known as "Henman Hill". And maybe it is no coincidence that it is at Wimbledon where Henman has had his best achievements in tennis.

Support from the crowd can lift a player to new heights. "When you are confident on the court, crowd support makes you feel even better, invincible; but if you are playing poorly and have little confidence then crowd support can add pressure," said Pam Shriver, a five-times Wimbledon doubles winner with Martina Navratilova.

"It is always better to have support. While I never experienced a horrible situation with the crowd against me, I played many times against a beloved player like [Evonne] Goolagong who received great support. My best memory of crowd support is the year-end championships at Madison Square Garden where 17,000 people were on hand and 90 per cent of them were for me, a US player who was the underdog. It helped me pull off the upset [over Steffi Graf who was the Golden Slam winner]."

The behaviour of the crowds at Wimbledon has changed over the years. Once it was polite applause for both players and a reverential hush during pauses in play. Nowadays the crowds are becoming much more partisan and dress up in national colours to support their favourite players, waving flags and homemade banners. Breaks of play are marked by chants, cheers and Mexican waves. When Henman or fellow Briton Greg Rusedski play, the stadiums are awash with a sea of red, white and blue.

But such nationalistic fervour is not just confined to the now no longer restrained British. In last year's memorable Wimbledon Final between Goran Ivanisevic and Pat Rafter, both players had their armies of supporters. The Australians brandished blow-up kangeroos and displayed their banners, while Ivanisevic's supporters waved Croatian flags. Chants of "Goran, Goran" and "Aussie, Aussie, Oi, Oi, Oi" resounded around Centre Court, creating an atmosphere resembling an ancient Roman gladitorial arena.

And at this year's Championships, there were almost as many flag-waving South Africans supporting Wayne Ferreira in his third round match against Henman as there were Britons backing their hero. Number one seed Lleyton Hewitt can also count on huge support from his fellow Australians, bedecked in green and gold, whenever he plays a match at Wimbledon .

It is a curiosity that some players are supported and others are not. Last spring, the Williams sisters earned the ire of fans when Venus defaulted to Serena because of an injury, minutes before their semi-final encounter at Indian Wells. "Whether I'm being booed or not, I've been through it," Serena explained at Roland Garros last year. "I just took it as an experience. I do have a lot of fans out there. Someone told me for everyone that boos, there are three people cheering. I keep that in the back of my mind."

Venus, who is looking to claim her third consecutive Wimbledon title, admitted: "It doesn't seem that often that I'm the player the crowd wants to win. Who knows, maybe there will be a day when they root for me."

During a visit to Wimbledon last year, former US president Bill Clinton put The Championships in perspective when he said: "This is still the greatest tournament in the world. There's nothing like it and everybody knows it. Even people like me, who don't play tennis anymore, sit around and wait for Wimbledon every year."

He could have added, "and so do the crowds".

Additional reporting by Mark Winters