The Japan Open tennis finals are here, but where are the fans?

Featuring some of the most skillful and marketable athletes in the world, professional tennis events regularly draw huge, excitable crowds, appealing to locals, tourists and even those with only a passing interest in the sport. Not so in Tokyo.

Instead, even an excellent women’s final last Sunday, and men’s early round matches this week featuring stars such as Rafael Nadal and Andy Murray in top form, couldn’t fill half the seats at the 2011 Rakuten Japan Open, held at Ariake Coliseum in Odaiba, a mere 20 minutes by train from Shibuya.

On the plus side, those empty seats make for a surprising opportunity for anyone looking for a shot of pro sport in Tokyo this weekend.

Grassroots withering?

While the players are teenagers or 20-somethings, and millions of Japanese kids play tennis at school, most fans at Ariake are over 50, and many have been attending since the Japan Open began in 1973.

Tennis fans in Ishinomaki spent weeks clearing tsunami debris off their court.

Though bigger crowds could turn out this weekend if Nadal and Murray reach the finals, the scheduling hasn't been kind to promoters either.

Japan’s most popular male player, Kei Nishikori, ranked 47th in the world, lost his first-round match Tuesday to number-three seed David Ferrer of Spain, quickly draining local interest even further.

Trained at the Nick Bollettieri Tennis Academy in Florida, Nishikori says the world tour doesn’t give him enough time to build grassroots support in Japan as golf sensation Ryo Ishikawa does.

“It’s hard for me to come back and play more in Japan,” he says. “I don’t know if I alone have the power to fill a stadium.”

Both the men’s and women’s events occur during the busiest week in the Japanese sports calendar, when too many circuses, including baseball playoffs and a Formula One race, happen all at once. NHK’s sports program on Sunday covered the Japan Open of women’s golf, but not the tennis.

Even worse, China has recently launched its own tournaments that steal away players like top-ranked Novak Djokovic and Roger Federer, who has skipped Japan every year since winning in 2006.

Raising awareness

Nobody is faulting this year’s players, who came to Japan despite radiation fears. “We all love playing in Japan,” says women’s finalist Vera Zvonareva. “We are also trying to raise awareness (for disaster victims) and raise some funds to help give back to them.”

Poland’s Agnieszka Radwanska, who won the Toray Pan Pacific Open in Tokyo last Sunday, seems tailor-made for Japanese consumption.

After running rivals ragged for a week to reach the final, Vera Zvonareva received a bouquet of fake flowers.

Unlike the brawny Zvonareva or Serena Williams, Radwanska is cute, petite and fast. Yet her ponytail was rarely seen on Japanese TV last week, and many Japanese girls who idolize Maria Sharapova still haven’t heard of Radwanska.

Even defending champion Nadal, who grew up in Spain watching the Japanese anime "Dragon Ball", could only fill half the seats during his win Tuesday over Japan’s Go Soeda, who is ranked 118 in the world.

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Japan’s current national champion, Yuichi Sugita, who nearly upset Canada’s Milos Raonic on Tuesday, blames “the mentality” of Japanese players, who don’t train hard enough to succeed on the world stage, he says.

“The place is perfect," he says. "We have everything we need, a national training center with a really good gym. But we need more hard work.”

It’s a common theme. The organizers and promoters should perhaps also work harder to adapt to changing times.