By Martyn Herman
(Reuters) - Tokyo's morning rush-hour will probably have flowed a little smoother than usual on Tuesday as millions delayed their journeys to find a TV beaming a 24-year-old wielding a tennis racket on a patch of concrete in a suburb of New York.
A tennis player temporarily halting the daily frenzy of life in one of Asia's heaving cities would have seemed fanciful a decade ago before Li Na became an icon for millions of Chinese sports fans with her landmark win at the 2011 French Open.
Three years on and in the season Li added the Australian Open title to her collection, Kei Nishikori's run to the U.S. Open final has shown that the acceleration of Asia as a tennis force is not restricted to the women, even if the men are still playing catch-up.
Nishikori's hopes of winning a maiden grand slam title were ruthlessly crushed by Croatia's Marin Cilic in the final on Monday, but his dream of becoming the first man from an Asian country to win one remains very much alive.
The Japanese, at 24, is still a young pup in tennis terms.
Six years ago he won an ATP tournament in Florida - the first by a Japanese player for 16 years - announcing himself to a nation obsessed with soccer, baseball and golf.
Since then, the ebbs and flows of life as a tennis professional have caused some to question his progress despite ringing endorsements from the likes of Rafa Nadal, Roger Federer and Novak Djokovic.
Until this year, that is.
With Michael Chang - an Asian hero for winning the 1989 French Open despite being American - guiding him, victories over the likes of 17-times grand slam champion Federer have propelled Nishikori into the world's top 10.
At the U.S. Open he truly came of age, becoming the first Japanese man, and the first from an Asian nation, to reach a grand slam singles final.
He did it the hard way, too. Consecutive five-set wins against Canadian giant Milos Raonic and Australian Open champion Stanislas Wawrinka were followed by a dismantling of world number one Djokovic in the semi-finals.
If it was not already, Nishikori's career, and status as an Asian superstar, is soaring into the stratosphere.
Just as Li Na and the likes of this year's U.S. Open semi-finalist Peng Shuai have done for an increasingly affluent Chinese middle class, Nishikori is now doing the same for a generation of Japanese not exactly short of distractions.
In short, tennis has become a "cool" choice for youngsters dreaming of a career in professional sport.
There is even a popular manga series in Japan featuring wannabe tennis champions. In Nishikori, the children have a new superhero.
"It's huge for Japan," Djokovic, who wears kit supplied by Japanese clothing label Uniqlo, further proof of the rise of tennis in Japan, said after his Flushing Meadows defeat.
"It's a big country. Over a hundred million people. This can definitely be a great encouragement for tennis in that country."
The development of Asian women's tennis, first with a plethora of Japanese players such as Kimiko Date-Krumm, still going strong at 43, and Ai Sugiyama, then the Chinese joining the party, has been more dramatic than the men's.
Until Nishikori, Shuzo Matsuoka had been Japan's most successful male player in the professional era - reaching the Wimbledon quarter-finals in 1995 and 46th in the world rankings - hence the "Project 45" tag given to Nishikori as he moved to the Nick Bolletieri academy in Florida as a teenager.
Before Matsuoka, the story of men's tennis in Japan was an unremarkable one - barring the tragic events of 1933 when world number three Jiro Sato, a five-times grand slam semi-finalist, jumped to his death off a boat in the Straight of Malacca on his way to a Davis Cup tie in Europe.
Elsewhere in Asia, powerful Thai Paradorn Srichaphan briefly made the top 10 in 2003 before disappearing while Taiwan's 37th ranked Lu Yen-Hsun has enjoyed a solid, if unspectacular, career.
No Chinese men regularly compete on the ATP Tour, although it hosts the Shanghai Masters Series tournament and another 500 series event at the 2008 Olympic venue in Beijing.
Indian players like Mahesh Bhupathi and Leander Paes have enjoyed doubles success but the cricket-mad country has no one like Nishikori waiting to capture the imagination of its youth.
The men's ATP is licking its lips at the thought of a player equipped to fire up markets ripe for a tennis explosion.
"As the head of a global sport organization we are always looking for diversity in where players are coming from," ATP executive chairman Chris Kermode told Reuters.
"Asia has always been a big focus. It's ripe now, it's a relatively young market and when you get a popular player like Kei coming through its very significant."
"He's paving the way for future generations to follow."
Nothing will be guaranteed though, with the bar being raised higher and higher.
Former Indian player Vijay Amritraj, famous for nearly beating Bjorn Borg at Wimbledon in 1979 and later appearing in a James Bond movie, says Nishikori has bucked the trend.
"Nishikori has been knocking on the door for a while. With Asian players they are often at a disadvantage with the physicality. Men's tennis is very physical and that obviously suits the plus six-footers," he said.
"But I think Nishikori is perhaps the first Asian player, maybe Paradorn did too for a while, to be able to tackle the ball early and play a baseline power game. He knocked Djokovic backwards on Saturday so that shows how strong he is.
"He's not a big guy but I think he has shown other Asians that with hard work it's possible to compete."
Japan opened a National Tennis Centre in 2008 and the sport will see further investment in the build-up to the Tokyo Olympics in 2020.
The Japan Tennis Association is well aware that in Nishikori they have some gold dust - and need to maximise the opportunity to inspire more players.
Nao Kawatei, tournament director of the Japan Open and chairman of the country's Davis Cup and Fed Cup committee, says Nishikori's achievements in New York could be a watershed.
"The history of tennis in Japan is long but now is our time," he said in an interview with the ITF's magazine.
Nishikori, whose already huge earning potential is about to go through the roof, said after reaching the Madrid Masters final earlier this year against Nadal that many back in Japan did not realize tennis was such a big deal.
They do now.
(Reporting by Martyn Herman; Editing by Ken Ferris / Frank Pingue)