Full coverage: 2016 Rio Paralympic Games

Five-a-side football, also known as futsal and blind football, is an adaptation of the beautiful game for athletes, who are visual impaired. And the sport is one of the most exciting at the Paralympics.

Different from normal football, the ball is equipped with a noise-making device, allowing players to locate it by sound.

Wang Ya'feng, who is participating in his third Paralympics, was surprised that he could use his ears to play.

"I never imagined that blind people can play football. I was surprised and also happy that there is a sport for people like us," he said.

With the specially-made ball, players can perform mesmerizing tricks with their feet, and accurately pass the ball. But they need a sixth player to guide them towards the goal. That person is positioned off the pitch, and assists in directing players.

"We are the eyes of the blind players. I'm responsible for instucting them in the direction of the goal, the movement of the ball, and the overall status on the pitch," said Wang Guishun, Chinese Blind Football Team guide.

Whereas mainstream football around the world is played admist a colorful backdrop, and in front of loud crowds. Etiquette dictates that spectators remain quiet unless the ball goes out of bounds, because players need to be able to hear each other and the ball.

Because the athletes have different levels of visual impairment, the players must wear eyemasks. Touching an opponent's eyemask is also considered a foul.

"There is another layer inside the masks, so that everyone has the same view. We also have to wear helmets to protect ourselves from colliding into one another," Wang Ya'feng said.

All of these nuances gives the game a hypnotic quality that makes it easy to forget that the players can't see what they're kicking.

Team China, who beat Spain and Mexico in the first two group matches, have secured a place in the semi-finals. They will face Argentina later on Tuesday, their toughest opponents of the group stage.