Sometimes it seems that there is a whole different ball game out there. And that game is squash.

Rafael Nadal has started playing it more this year. Roger Federer has just been getting better and better. The champion, though, may well be Fabrice Santoro, of France, who was knocked out in the first round by Andy Murray, another decent-looking squash player, three days ago.

We are talking here about the use of the wrist. Any beginner given the traditional start to tennis will be taught to lock the wrist, to hit groundstrokes as if the hand is an extension of the forearm. Yes, roll the wrist, but not do not break it, do not use it as a hinge. Do not play squash.

But in the ever-changing world of technique, the wrist hinge has found its way through the gates of the All England Club. It arrives as a collective product of new technology, better athleticism and sheer desperation to keep the ball in play. But you would never have seen Pete Sampras, the American who won seven Wimbledon titles and an equal number of other grand-slam events, playing it.

As Greg Rusedski, the former British No1, said: “In our day, maybe we just weren't good enough to do it.”

The specific shot he is talking about is played off the forehand, wide out on the stretch, in an attempt to reach an out-spinning serve or, more likely, a cross-court drive. “If you're dragged out wide and you've got no chance to get a racket on it properly, you can either throw up a lob and most likely watch someone bury it, or you can alter your grip and play a squash shot,” Andrew Castle, the BBC presenter and another former British No1, said.

Castle should know about squash because, 16 years after retiring from professional tennis, he is still playing squash for Surrey. It was Castle who taught Stefan Edberg to play squash when Edberg was living in London; Castle plays Tim Henman at squash and on Sunday morning has a court booked to play Henman's brother.

“That stiff wrist thing has gone in tennis,” Castle said. “The squash shot is not something you practise. It's a last-resort shot but, increasingly, more players are using it.”

The squash lobby has noticed this, too, notably Peter Nicol, the former world No1. “Yes, they are clearly adopting squash techniques, the use of the wrist shots, especially on grass,” he said. “Both squash and tennis have got quicker and quicker and you have to adapt and mix it up. You can't just use the old techniques any more. Federer once said that a lot of his different shots were from his days playing squash.”

His reference is the French Open semi-final of two years ago, Federer versus David Nalbandian, when the Swiss ran back to chase a lob and pulled off a forehand pass from the baseline with his back to the net. Afterwards Federer put it down to the squash that he played regularly as a child with his father.

“I imagine that a lot of other players then thought, ‘If it works for him, then why not me?'” Nicol said, going on to suggest that tennis players would benefit from studying squash. “It would be good to get them to watch a top, live match and understand what works,” he said. “I think that would really help them.”

The squash influence is not new. Ivan Lendl, the Czech former world No1, used to play the sport to strengthen his backhand. Murray played squash as a child in Dunblane, but he has a mother, Judy, who carefully schooled him and his brother, Jamie, in the arts of spin and touch that are so closely related to squash.

“I taught them a lot of the different skills so they both can slice and drop-shot pretty well,” she said. “I was always very aware that if all you can do is rally big and hard, what do you do if you come up against someone who does that better? For example, this squash-looking shot has evolved to counter the cross-court forehand.” The point, though, is that more and more players are incorporating it. Why now? Because technology has produced rackets that allow them to. And, as Rusedski explained, because the new generation have the physique to match. “These guys are so strong,” he said. “Look at Federer and Nadal, they are probably the strongest guys to have been at the top ever.”

So watch for the wide-out squash flick. “Obviously Federer and Nadal do it,” Castle said. “Juan Carlos Ferrero is brilliant at it. Andy Roddick can flip a squash shot, too. But Santoro - virtually every shot he plays is squash. If he did play squash, what a nightmare he would be.”