Boxing is booming in Japan. Naoya Inoue is leading the way as one of the finest fighters on the planet and 14 world titles presently reside in the land of the rising sun.

The day before Inoue smoked Mexican Luis Nery in May, climbing off the floor to win a thriller in the Tokyo Dome in front of tens of thousands of fans of all ages, Ryosuke Nishida claimed the IBF bantamweight championship in just his ninth pro fight a couple of hours away in Osaka.

Then, on the Inoue-Nery bill, 8-0 Yoshiki Takei, a former kickboxer, dethroned Australian Jason Moloney to claim the WBO bantamweight belt. Inoue, of course, had won his first title after just six fights.

Unified junior featherweight champion Inoue, is joined by WBC bantamweight champion Junto Nakatani, WBA bantamweight champion and brother Takuma Inoue, IBF bantamweight champion Nishida, WBO bantamweight champion Yoshiki Takei, WBA junior bantamweight champion Kazuto Ioka, WBO junior bantamweight champion Kosei Tanaka, WBA flyweight champion Sigo Yuri Akui, WBC and WBA light flyweight champion Kenshiro Teraji, and IBF minimum flyweight champion Ginjiro Shigeoka.  

The lower divisions are also filled with Japanese talent at varying stages of their careers. Winning an Oriental and Pacific Boxing Federation title ensures a fighter of a spot in the rankings, but the lower weight classes are chock-full of largely impressive Japanese fighters.

At minimumweight, at the time of writing, WBC No. 2 Yudai Shigeoka is 8-1, WBA No. 8 Masataka Taniguchi is 18-4, WBC No. 10 Goki Kobayashi is 7-1 and WBC No. 15 Yuni Takada, born in the Philippines but living in Japan, is a comparative veteran at 14-8-3 but has won his last six.

Takada is also ranked by the WBA and the IBF. Yudai Shigeoka is ranked by the WBA at No. 3.

Up at junior flyweight, 12-1 Shochiki Iwata, 6-0 Kyosuke Takami, Masamichi Yabuki, 16-4, 6-0-1 Yuga Ozaki and 10-1 Toshiki Kawamitsu are all ranked by at least either the WBC, WBA, WBO or IBF. 

At flyweight, there’s 18-2 Hiroto Kyoguchi, 13-2 Taku Kuwahara, 6-1 Jukiya Iimura, 15-0 Kento Hatanaka and Riku Kano, 22-4-2 among the rankings. 

Ten of the 12 titles from junior bantam to super bantamweight are held by Japanese boxers.

At junior bantamweight, there are 8-0 Suzumi Takayama, 12-3-1 Tetsuro Ohashi, 24-5-1 Kenta Nakagawa, 6-1 Takahiro Tai all vying for spaces in the ratings.

At bantamweight, where the Japanese have a sweep of the major titles, there’s 3-0 Tenshin Nasukawa (he of the infamous Mayweather exhibition), 10-0-2 Seiya Tsutsumi, 18-8-1 Keita Kurihara, 34-4 Sho Ishida, and 4-1 Riku Masuda. 

At junior feather, where Inoue wears all of the gold, there is only 18-1-3 Toshiki Shimomachi in the ratings of any of the four sanctioning bodies, but at featherweight the ranks are again bursting when you factor in 10-0 Keisuke Matsumoto, 41-4 Tomoki Kameda, 25-4-1 Reiya Abe, 5-0 Hayato Tsutsumi, Shimomachi (ranked here again), and 7-0 Kenji Fujita.

At junior lightweight, 15-1 Masanori Rikiishi, 28-2-1 Kenichi Ogawa, are rated by the WBC, IBF and WBO respectively.

Other fighters through the rankings include junior middleweight Takeshi Inoue, welterweight Jin Sasaki, super lightweight Andy Hiraoka, and lightweight Katsuya Yasuda.

And it is not just a matter of getting to the top, it is how quickly many have been able to achieve it with almost 20 Japanese fighters becoming a world champion with less than 10 professional fights to their name.

Kosei Tanaka did it after just five in 2015 and Inoue did it in six just a year earlier. Kazuto Ioka did it in seven in 2011, and last year Yudai Shigeoka managed it in eight fights, the same number it took Nobuo Nashiro in 2006, Joichiro Tatsuyoshi in 1991, Satoshi Shingaki in 1984, Hiroto Kyoguchi (2017), and Kosei Tanaka in 2016.

In 1976, Yoko Gushiken did it in nine fights, which was matched by Hiroki Ioka in 1987 and Nishida a couple of months ago.

Australian matchmaker Mike Altamura explained Nishida’s path. 

“Nishida was a very well-credentialed amateur," he said. "A lot of what’s achieved in the amateurs and in the university system in Japan flies under the radar internationally, but he’s been considered a hot prospect for a long time, and in his third outing he beat Shohei Omori, who is a two-time world title challenger and that was at 122. 

“He beat the former world flyweight champion Deiko Higo over 12 rounds in his fourth fight, so when you see people achieving things of that ilk, you realize they’ve got the ability to be very precocious and very special and I felt that the smart thing within the team was there could have been that rush, maybe after four fights, five fights, six fights, [to go for a] world title… I felt that those four fights gave Nishida a lot more hardening and time to build as a fighter, and I think you saw the fruits of the labor.”

It is still early days for Nishida, but he already appears a well-rounded champion who has versatility and courage as well as skill. 

“I expected the victory, I just didn’t expect 12-round trench warfare,” Altamura added, in discussion of Nishida’s title win over Puerto Rican Emmanuel Rodriguez. 

But, of course, Nishida is not a unique example, just another star to be built on an impressive assembly line.

Daisuke Sugiura, writer for The Ring, has seen improvements in the sport in Japan from the bottom to the top, and because of what happens at grassroots level, the sport is thriving on the big stage.

“The enhancement of the youth system has produced great results,” Sugiura states. “That’s probably the most logical explanation. My friend Issei Nakaya, the chairman of Hachioji-Nakaya Gym, gave me this quote: ‘It was really huge that the Japan Boxing Association started a tournament for juniors [up to junior high school students] 15 years ago, and the tournament evolved and is now being called the JCL [Junior Champion League]. Naoya and Takuma Inoue, Kousei Tanaka, Junto Nakatani, and Ginjiro Shigeoka are all world champions with experience in this tournament. Naoya Inoue is the winner of the first National U15 Tournament. I think this is a result of the fighters who have built their careers there growing up as expected.’ 

“Additionally, the advent of the streaming era has made Japan boxing more financially plentiful, allowing Japanese fighters to have more world title fights than ever before. Last, not least, we should not forget the efforts of some promoters, most notably Mr. Honda of Teiken USA. Mr. Honda is respected by everyone in this business. Some big fights, include Ryota Murata vs. Gennady Golovkin and Nayoa Inoue vs. Stephen Fulton, would not have been possible without Mr. Honda's influence.”

Japanese boxing historian Joe Koizumi agrees. Koizumi has chronicled the sport for more than half a century and has seen many of the Japanese greats. He has also witnessed important structural changes to the boxing landscape in Japan. Koizumi was inducted into the International Boxing Hall of Fame in 2008.

“Because Japanese professional boxing and amateur boxing have different associations that help each other, for example, amateur boxing cultivates young boxers and some very good young boxers get established in the amateur field, like winning Olympic medals or national championships, afterward they move and then they enter the paid ranks as professionals and they have the fundamentals, the technical fundamentals,” Koizumi explains. 

“A very good example is Naoya Inoue. When he was at high school, he won national championships, then there’s Murata, Olympic medallist, also established a good name in the amateur field. After winning the gold medal he entered the professionals with Teiken Promotions and Mr. Honda and he’s very influential and he established Murata in the professionals and gave him good opportunities to win a world title.”

Altamura also believes the university system in Japan is a stimulus to the development of the fighters and aids their progress inside and outside the ring. 

“Essentially its athletes who fight on the university teams, you secure a scholarship but there needs to be legitimate study components to it, so it’s not like some of the footballers on NCAA scholarships that are 90 per cent football and 10 per cent students,” Altamura says. “In Japan, it’s very harsh in that you’ve got to keep your grade averages up and learn a trade. That’s why you see a lot of these fighters that excel in the university system, they turn pro at 23 or 24 years of age, sometimes even later, because they legitimately have a very strong foundation behind them. Very well educated. 

“But you look at the fighters that have emerged out of it, there have been so many top tier fighters throughout the years. You think of like the USA system for something like volleyball, basketball, football, it’s that same kind of breeding system where a lot of the elite Japanese amateurs who want to pursue education, too, are drawn to that system. So it’s not where you think, ‘Alright, you’re fighting in this university and your opponent maybe particularly weak’. The standard is exceptionally high.”

This week Nishida, a former Kindai University student, took his IBF belt back to the campus to inspire the next generation of champions. 

Japanese journalist Aogu Tanaka also highlighted the importance of the Under-15 tournaments for progression.

“Some people, including Ohashi Gym where Naoya Inoue currently belongs, have been holding a junior boxing [U15 national] tournament for about 15 years,” Tanaka adds. “As a result, a sense of competition was born and developed in the amateur boxing world. This is probably a big reason why a lot of successful boxers have emerged.

“Furthermore, there are cases where kickboxing talents switch to boxing, and it seems that a large number of these are fighters with strong backbones turn to boxing professionally.”

It was not, however, always like his. 

“To be frank, about 20 years ago, the professional and amateur worlds weren't so close,” Tanaka admits. “However, as more and more fighters turn from amateurs to pros and become active, their relationship has improved. It has become common for promising amateur athletes to join famous gyms.”

This is not lost on Koizumi, either.

“Some 20 years ago amateur boxing and professional boxing was very much separate,” Koizumi continues. “They would antagonise one another. Why? Professional managers, promoters, and scouts exploited good prospects out of the amateurs. They might have been good candidates for winning Olympic medals, but managers pulled them out of the amateurs, for example Takao Sakurai, the first Olympic gold medallist in amateur boxing tried to keep separate in the amateurs and said he would not go to the professional field, his style was quite amateur, but Sakurai then wanted to try his fist in the professional field. He had this good opportunity against Lionel Rose of Australia. 

“Sakurai scored this early knockdown, but he tried to keep that point lead, running around the ring and it was a split decision or majority decision he lost.

“Kiyoshi Tanabe, Olympic bronze medallist, retired unbeaten because of a detached retina, but he was a very excellent boxer. Also, Kenji Yonecura, who challenged Pascual Perez for the flyweight title and Jose Becerra for the bantamweight title, twice. Yonecura failed, twice, but his manager and promoter cultivated good boxers. One of them is Ohashi.

“When Fighting Harada was boxing, they graduated from junior high school, then, at the age of 15, they worked, and after working they trained to be professional boxers and Fighting Harada became world champion at the age of 19. The majority graduate from high school and go to university and education is very hard but after graduating from university at the age of 22, they have good amateur records and then enter the professional ring. 

“Some of them are successful, becoming national champions, Oriental champions, Asian champions, some of them try to challenge the world champions.”

Koizumi also says that the amateurs “eliminate the boxers who are not set up to be successful in the professional field. Some amateur boxers, excellent ones might be just good technically but they will not have success in the professional sphere, so they quit after their amateur career”. 

But it is not just the structure that breeds the champions; it’s the culture. Both Altamura and Tanaka see varying Japanese attributes as being advantageous in boxing.

“It is important that we have good personnel in the lighter divisions,” Tanaka explains. “Japanese people have small bodies and are often suited for lightweight classes. Inevitably, good boxers tend to emerge in the lighter divisions.”

“Most of them are smaller fighters and the matchmaking for them is easier,” adds Sugiura. 

Altamura states: “I think that the culture brings discipline, and so when you have someone that’s in shape and condition year-round, they’re going to improve rapidly. And that has the ability to fast-track them through the rounds, but also what I love about Japanese boxing is losses aren’t demonized. Camps over here are more prepared for risk, whereas you sign a 5-0 boxer to a major westernized promoter and they drop, say, an eight-round decision to someone with a similar record or more experience, it’s generally perceived as a big setback. 

“In this system, there’s not that same. As long as you bring the right fighting spirit and effort and preparation, you’re not demonized as harshly for your losses, and I think that almost gives more of a sense of it being a free-hit. And sometimes it might backfire, but the Japanese tend to get it right, more often than not.” 

A further point worth exploration is that this now-vaunted amateur system takes fighters to a high level without leaving them drained, dilapidated or burnt out. Some amateur systems result in their young fighters having hundreds and hundreds of fights. That is a lot of damage and trauma and the odometer is ticking at quite a rate before a punch is landed in the pros. The case is not the same in Japan.

“Japanese fighters will generally have less amateur fights, like the elite Japanese amateur fighters that turn pro in their mid-twenties, will have considerably less fights than an elite Ukrainian, an elite Russian, an elite Cuban, so I think it would generally be between 30-80 fights,” Altamura estimates. 

“Less than 100 fights,” Koizumi opines. “Amateur boxing, especially in Japan, is respected for its safety. They stop fights very early to avoid ring tragedies.”

For tragedies, see also wear and tear. 

That is also kept to a minimum in gyms. While some trainers in the West might brag about being able to sell tickets to see wars in their gyms, those struggles from behind closed doors further borrow from a fighter’s future.

“Basically, there is a lot of instruction that emphasizes technique; additionally, in the past, spirit was thought to be important,” Tanaka says. “In recent years, in addition to these two, the importance of physical training has also been recognized and incorporated.”

Altamura has seen that improve, too.

“I do think they’re more preserved, but also conditioning’s key,” he says. 

“They keep condition year-round and I see the way things operate in the gyms in Japan, and again it’s something we need to take stock in because not every sparring session is a fight for your life. There’s a lot of internal training, a lot of drill-based sparring, and I think that also preserves the fighters for being battle ready and fresh where it counts, which is in their fights.” 

Even the organization of the gyms is unlike what you might find in the U.S. or in Europe.

“The system is totally different,” Sugiura adds. “Usually, the chairman of the gym is the manager of the fighters who belong to the gym. Mr. Honda or Ohashi can be both managing and promoting.”

Tanaka goes further: “In many cases, the promoter and gym chairman are integrated. This is almost always the case at famous gyms in Japan.”

That often sees a team formed and pulling in the same direction and, for want of a cliché, being on the same page.

The team environment also helps. Inside the Tokyo Dome for Inoue-Nery, fighters from the Ohashi gym sat together in red tracksuits. They were united, as if on a school trip. They were a team, and it goes deeper than that, too.

“There are various classes [levels] of boxers in Ohashi Gym… Teiken Gym,” Koizumi points out, “they choose good examples of fighters themselves. The young boxers look to them and follow their example, technically and mentally.”

It is called a “brother system” and sees intelligence, experience and support gifted from fighter to fighter and generation to generation.

“Ohashi cultivated Kawashima, junior bantamweight champion, also Akira Yayagashi, they gave this to [Naoya] Inoue and he respected them and followed their advice. 

“It’s the brother system, and they give advice to the younger generation, now Inoue gives good advice to the younger generation.”

Of course, Inoue is the centrepiece of the Japanese revolution. The boxing world stops when he fights, and he is a rare boxer who has universal approval and respect as one of the three best fighters in the world, alongside Terence Crawford and Oleksandr Usyk.

If there is a Japanese conveyor belt of talent, the end product is Inoue.

“Hard to overstate his importance,” Sugiura says, of the impact Inoue is having in Japan. “By far the most popular and marketable fighter in Japan. Simply, boxing becomes a major sport in Japan when he fights.” 

Tanaka agrees: “He is definitely considered a legend. Even if he is not as good [big] as Shohei Otani, who plays in MLB, he can be comparable. I think he might be in the top three in terms of popularity among Japanese male athletes.

“Almost everyone knows Inoue's name, even people who aren't interested in sports.”

Yet, for all of its success, boxing still does not challenge other sports on the whole in terms of leading the way in the mainstream. Inoue fight nights cause the nation to come to a standstill, and other boxers – like Nakatani – create a serious stir. But the snowball has yet to fully transform into an avalanche. 

“Although it is not as popular as baseball and soccer, which are popular sports in Japan, its popularity has increased in recent years due to the appearance of Naoya Inoue,” Tanaka says.

“I still hesitate to call it a fully-fledged major sport. Very few people in the business are making big money, and baseball, soccer, sumo, golf, tennis, figure skating and other sports are bigger than boxing,” adds Sugiura, somewhat starkly. “That being said, we have a legitimate superstar in Naoya Inoue and there also are a lot of quality fighters. All in all, I think the state of boxing in Japan is similar to that in America. It doesn’t usually get a lot of attention and is more of a niche sport, but several times a year, many people take an interest in the big events and get excited about it.”

Regardless of exactly how big it is, and how much Inoue might carry it to the masses, Mr. Honda told me recently that the future is bright and the wider world has not heard yet of the best fighters who are still coming through the ranks and ready to step off this incredible production line.