For a few years now, the Hawk-Eye system has helped to determine IF a ball is in or out in a big tennis match.

Very soon players at all levels of the game may also know WHY their ball sailed wide or long.

That, at least, is the vision of Eric Babolat, CEO of the French tennis equipment company Babolat, who has introduced the first “Connected Racquet” in the sport.

Designed for pros and amateurs, and tested by the likes of men’s number one Rafael Nadal, Jo-Wilfried Tsonga and Australian Open champion Li Na, the racquet gathers data through sensors and chips in the tube.

Approved by the International Tennis Federation for use since January 1, Babolat expects to see the first professional players using it at tournaments from mid-year.

Amateurs can purchase the racquet – which does not differ in size and weight from normal racquets – from May 15 onwards in Europe, at E399 ($A600).

“It adds value without changing the game,” Eric Babolat told DPA at the WTA event in Stuttgart.

Technology is more and more entering all aspects of sport, from the Hawk-Eye system which is now also used in football, video replays or data-gathering in running with chips attached to shoes and apps for smartphones or tablet computers to analyse the training or competition.

Babolat, whose company started out in 1875 making racquet strings (two years before the first Wimbledon), launched development 10 years ago, before the arrival of smartphones and apps.

“Ten years ago you would test with a backpack and cables,” he recalls.

Rapid improvement in technology led to development based on the simple idea that “the racquet has an empty tube.”

Chips and sensors finally became small enough to fit into the racquet, but Babolat freely admits that “developing an app was a completely new world for us.”

The sensors are to show players how hard and cleanly they hit. They determine between backhands, forehands and serves, and all data can be transferred via bluetooth or USB cable to the app after training or matches.

Players can compare themselves with others in the app-community if they wish to do so.

“It enriches the game. It is interesting for pros and club players. You just want to know at what level you are,” Babolat said.

Nadal said in a video “you have the chance to know much more about your tennis.”

Babolat said the top players have embraced the system saying they “were like little kids playing with something new.”

A coaching app is now planned and Babolat expects other companies to follow.

“In 10 years you won’t have any racquets that are not connected,” he said.