Few people know Carlos Alcaraz better than Kiko Navarro, the coach who shaped the Spaniard in his formative years into the fearless world number one targeting a second Grand Slam title at the French Open.

The 38-year-old Navarro continues to teach tennis at the El Palmar club in Murcia, the sun-drenched city in southeastern Spain where Alcaraz, 20, was born and raised.

It wasn't long ago that Alcaraz was his prized pupil, having coached the reigning US Open champion between the ages of nine and 17 before he linked up full-time with 2003 French Open winner Juan Carlos Ferrero.

"You know that Paris has always been our dream," Navarro whispered in the ear of Alcaraz as he bid him farewell two weeks ago after bumping into him just prior to his departure for Roland Garros.

On Friday Alcaraz will play 22-time Grand Slam champion Novak Djokovic in an eagerly-anticipated semi-final in Paris.

"I'll see it here at home," Navarro told AFP by telephone. "Unless tomorrow I unexpectedly go there..." he added, not ruling out the possibility.

Navarro is bullish about his protege's title prospects despite Djokovic standing in the way.

"I made a bet with his father that he would win Barcelona, Madrid and Roland Garros, I already have two out of three," said Navarro.

"He will beat Djokovic unless something strange happens, but he's coming into it in good shape so I don't think he'll get hurt."

Alcaraz's electrifying style draws plenty of admirers and Navarro says it's an approach that comes naturally to the Spaniard.

"If you stick on a video of the boy you'll see he plays like he does now. He was a prodigy technically, in this sense his development hasn't been spectacular," said Navarro.

"The forehand, the drop shot and the volley are innate. The serve has improved and the backhand cost him a little bit. Every now and then we briefly thought about changing it to one hand.

"His development has been physically. We were afraid he would stay small but he has grown to a good height and he is like a beast."

- 'Very bad loser' -

Alcaraz has set records tumbling and became the youngest men's world number one after last year's Grand Slam triumph in New York.

Despite the pressure of being the top seed at Roland Garros, Alcaraz has never lost his smile this fortnight -- a friendly assassin whose will to win is unrelenting.  

"At the age of 10 he was a very innocent boy, without any bad intentions on or off the court, very happy. But he didn't like to lose anything, he was very competitive," recalled Navarro.

"He's broken many racquets with me, he left the court crying and I had let him calm down before talking to him. He was a very bad loser, he wanted to also win at padel, at board games and at cards. But to be number one you have to be like that.

"The key was at 13 or 14 he realised that this was very serious. He had a cheerful, attractive game, wherever we went we were the centre of attention, both in Spain and in Europe.

"He was already well known, he was breaking Rafa Nadal's records... So we had to work a lot on the head, the motivation and humility."

It was a lot to take onboard but Navarro never doubted that Alcaraz had the character required to make it to the very top.

"I knew that because of his way of being and his tennis he was going to reach people, even more than Rafa, who is more serious. Carlos gives off more joy," he said.

"In the many hours we spent in the car or the plane, I always gave him talks so that he would continue to keep his feet on the ground. And I feel very proud. He knows where he comes from, his roots and who his people are. It's not easy to become a global star so quickly."

pm/dr/mw/dj