When Rafael Nadal was a young boy on the Spanish island of Majorca, he used to run home from school to watch his favorite Japanese anime -- "Dragon Ball."

The Toei Animation cartoon, adapted from a 1980s manga by Akira Toriyama, must have made an indelible impression on the young Nadal.

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Like Dragon Ball’s hero Goku, a martial arts student who came from an extraterrestrial race called Saiyans, Nadal has also come to conquer the world, or at least the tennis world, with an unorthodox style that he seemed to learn on another planet.

In fact, Spanish astronomers have even named an asteroid belt after him.

Goku on the left, Nadal on the right.

Dragon Ball inspiration

Rocketing across the court, twisting to hit winners from impossible angles, Nadal sometimes even looks like Goku, with his mouth open in a grunt that is both ugly and sexy for millions of his worldwide fans.

“It’s my favorite cartoon,” Nadal tells journalists in Japan who ask him about "Dragon Ball" after his opening round victory at his first ever Japan Open.

“I have all the DVDs, from the first one to the last one.”

A superhero with a hulking physique and intimidating glare, the feisty Spaniard is more raging bull than matador on the court.

As a Wimbledon commentator once said, Nadal is simply out to beat you on every point.

Playing under the yuyake evening fires of a Tokyo Bay sunset, Nadal seems to have learned tennis on another planet, as he twists to make impossible shots.

Islander charm

But off the court, Rafa has a simple islander charm in stark contrast to his friend and arch-rival Roger Federer, the sophisticated and multilingual cultural ambassador who wowed fans at the Japan Open in 2006.

Coming into the Ariake tennis center press room after his first round victory, the 24-year old Nadal, who has won more than $30 million on tour, apologizes like a schoolboy, “Sorry, I was a little bit late.”

He works hard to communicate clearly, and uses new words he has just learned, such as "cartoon."

While the former vegetarian Federer talked about Zen philosophy, Japanese proverbs, and playing tennis at the Imperial Palace, Nadal says stuff like “I don’t like shopping.”

On his off-day Wednesday, he played a few holes of golf but otherwise hung around the hotel trying to rest from a relentless year of touring which saw him win the French, Wimbledon and U.S. titles.

“Japan is one of the places you definitely want to know and hopefully I will be able to come back. The Japanese people are giving me a lot of presents. I’m just enjoying these days, on this very nice center court atmosphere,” he says.

Rafa-mania. Japanese fans crush around Nadal for autographs of balls, programs and even mobile phones.

Fan adoration

For tennis fans, who consider the Nadal-Federer rivalry to be among the greatest ever in sports, it’s amazing to hear Nadal say he doesn’t know if Federer is currently ranked number two or number three.

"It's very difficult to always be at the top," he says of Federer.

"What he did is very, very difficult. For me, I don’t think there’s a big difference being number one or number two in the world. My life doesn’t change. I’m still with my family at home. It’s a really normal life for me," he says.

"The best thing is not being number one in the world, it’s being healthy and being able to enjoy my life,” he adds.

Meeting Japan's leading light, Kei Nishikori

On the event’s opening day, Nadal got a surprise welcome greeting from Kei Nishikori, 20, Japan’s top prospect in years.

Though Nishikori lost his opening round singles match, and second round doubles match with partner Go Soeda, his popularity nearly filled the stands at Ariake Tennis Center in Odaiba in Tokyo Bay.

“I was very surprised to see so many people, even people who couldn’t get in. I just wish I could have played better,” said Nishikori.

Nishikori winces in pain after tweaking an elbow that required surgery due to his trademark “Air Kei” forehand.

Sent to an elite tennis academy in Florida at age 13, Nishikori, who was very shy early in his career, seems unusually footloose for a Japanese athlete. He often mixes English into his easy-to-understand Japanese -- saying phrases such as “play o suru.”

His mentor Shuzo Matsuoka, 42, Japan's greatest male tennis player ever and the son of the chairman of Toho film studio, which gave the world Godzilla and Akira Kurosawa, says Nishikori fortunately had friends from Japan who went to America with him.

“With men’s tennis you always have to be independent. Japanese, on the other hand, always adjust to people. We want to be part of a team” said Matsuoka.

Avoiding the media glare

Matsuoka says Nishikori is more comfortable hanging out in Florida with his buddies, away from the media pressure and expectations that he will become the Ryo Ishikawa of Japanese tennis.

After stunning the tennis world by winning a tour event in Florida at age 17, Nishikori ranked as high as 56th in the world before an elbow injury sidelined him for a half a year and changed the technique on his trademark jumping forehand, known as “Air Kei.”

"My arm is getting better so I think I can aim higher,” says Nishikori. “I am playing with all the big guys, all the top players, so mentally, I think I’m getting really strong,” he adds.

“I’m enjoying this moment, playing the tournament all week and training for all the big tournaments. It was really tough last year, but I learned a lot of things, and I played (Novak) Djokovic in the French Open and Nadal on center court at Wimbledon. I’m really enjoying my life,” says Nishikori.

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