The professional and amateur sides of Japan’s national sport came together last month with the founding of Tachihi Holdings Women’s Sumo Club.

With longtime NHK announcer Fujio Kariya as director, the club immediately signaled its intent by signing former sekiwake Toyonoshima to a one-year deal as head coach.

The first order of business for Toyonoshima will be helping Airi Hisano — currently the club’s only member — to reclaim gold at this September’s Sumo World Championships in Thailand.

Hisano topped the podium at the 2023 tournament but lost out in the semifinals to Iryna Pasichnyk of Ukraine last year.

Describing that loss as painful and detailing how she struggled with injury over the past few years, the former college sumo standout admitted she had considered retirement on more than one occasion before being approached by Kariya.

At a news conference following a training demonstration on May 1 at Tachihi’s new purpose-built dohyō in Tachikawa, Hisano said that after graduating from Nihon University, she was "debating whether or not to continue with sumo.”

Deciding to keep going, she trained in her free time with a former classmate while also working for a security company.

But after taking gold in October 2023 at the World Championships in Tokyo, the 172-centimeter, 125-kilogram veteran injured her back later that month at the World Combat Games in Saudi Arabia. The injury lingered, and she failed to reach the final of the 2024 World Championships in Poland.

“My goal had been to win a world title, but I hadn’t thought about what came after that. I had won the championship, my back was hurting, and as an athlete, the injuries would continue to pile up, so I was conflicted about what to do.

“It felt like time to call it quits, and I was close to retiring when Kariya contacted me last October.”

With few opportunities for women in Japan to continue in sumo once their college careers come to an end, Hisano decided to join the new club and work toward both her own individual success and growing the sport as a whole.

Hisano said that when told of Toyonoshima’s appointment, she was “really surprised but also excited because I had seen his bouts on TV.”

Despite having only had a few sessions together — she works weekdays in a corporate job — the former world champion is already seeing the benefits of training with someone who has so much high-level experience.

Describing herself as prone to overthinking, the Tochigi native said she appreciates Toyonoshima’s pared down approach.

“My technique isn’t great, but he explains everything in a way that is easy to understand,” she said.

When pressed for examples, Hisano cited breaking an opponent's grip on the mawashi.

"It’s not something I had given much thought to, but it’s a very important part of sumo," she said.

While Hisano has had to battle with much larger opponents from Russia and Ukraine, that physical gap pales in comparison to the one that Toyonoshima faced in professional sumo.

Over an almost two decade career, the 168 cm Kochi Prefecture native not only survived, but thrived while facing men 30 cm taller and 40 kg heavier than him.

In November 2010, he went 14-1, defeating Kisenosato, Kakuryu, Kaio and Baruto along the way before ultimately falling to Hakuho in a playoff for the Emperor’s Cup.

It’s a background that would seem to offer ideal insight for his new position, but the former sekiwake said that for now, he is focusing on the basics with Hisano and will leave advice about how to topple larger opponents for later in the year.

One of the difficulties for his new student is the lack of training partners with similar dimensions to the opponents she regularly faces in international competition.

According to Kariya, while it's possible for Hisano to train at university sumo clubs such as Nihon, Waseda, or NSSU, there are no women there able to offer the kind of physical challenge she needs.

It’s a major reason that the longtime face of NHK’s sumo broadcasts approached Toyonoshima to become head coach of his new club — though Kariya also said that seeing how smoothly and succinctly the former sekiwake explained what was happening when on the Hakuho Cup broadcast convinced him that he had the skills needed to be a good teacher.

There is of course one suitable opponent in Japan in the form of two-time defending heavyweight world champion Ivanna Berezovska — but the possibility of a training session with Hisano appears to be low.

The Ukrainian star, who came to Japan in 2023, trains at the Kyushu Institute of Information Sciences, but the distance from the capital isn’t the only obstacle.

“Of course if she came to Tokyo, I’d like to train with her,” Hisano explained. “But basically, I want to defeat her in a tournament. Wanting to beat her for real is the priority.”

The two faced off in the over-80 kg and openweight title deciders during last October’s All-Japan Women’s Championships, with the massive Ukrainian emerging victorious in both contests.

With a new sense of purpose, and a coach who knows more than perhaps anyone about taking down giants, Hisano will be looking to avenge those defeats in September in Bangkok.

Regardless of how that contest goes, however, the creation of a corporate team is a huge step forward for women’s sumo, and Hisano, Kariya and Toyonoshima are making history together as they attempt to grow the sport.