Accompanied by two women, 9-year-old Felipe Angiono enters cautiously and asks: "Is this where the blind play tennis?"

Upon hearing a "yes," Felipe responds: "OK, I found my place."

Felipe is attending his first tennis class for the blind, a form of tennis modified for the visually impaired and invented in 1984 in Japan by the late Miyoshi Takei.

"I'm blind from birth, but now I'm going to play tennis and hope to be the best," Felipe said, adding that Argentine player Juan Martin del Potro was his idol. "I want to be like Del Potro."

Felipe, with his mother Maria Laura and his grandmother Mercedes, is one of about 20 students taking lessons at Centro Burgales in the Buenos Aires neighborhood of Caballito. Ages range from 7 to 60, and many practice twice weekly on two courts.

The court is the size of a badminton court, the net is lower, and the rackets have bigger heads and shorter handles. The boundaries are marked by cords fastened to the ground so players can feel them with their feet.

The ball is made of foam and filled with metal pellets that rattle when hit. When the ball is served, it can bounce three times before being returned.

"I really like the sound of the ball, this tic-tac sound," Felipe said. "I also like the way players scream when they serve."

Gustavo Alonso, a 50-year-old man, practices near Felipe. He began losing his sight in 2006 and took up blind tennis recently.

"When I started playing 1 1/2 years ago, I did it for entertainment and if I missed the ball I wasn't worried," Alonso said. "It seemed I was trying to net butterflies. Now I have more drive and courage and always want to win."

The founder of the sport in Argentina is Eduardo Rafetto, who said he started researching blind tennis after a woman with two visually impaired daughters asked him if they could play tennis.

"I was looking for something about it on the Internet and discovered it in Japan," Rafetto explained. "I put myself in contact with them, and that's how it began."