For this article, we spoke with Kashima Antlers Director Masaki Hamaguchi (@hamagucci), whose involvement with the club began during his tenure as Mercari’s head of Sports Business. In our conversation, @hamagucchi walked us through the synergy between Mercari and Kashima Antlers and how the two partners elevate each other.

IT and sports: a clash of different languages

—To start off, how did you come to work with the Antlers?

@hamagucci:  I was first assigned to work with the Antlers in my role as head of Mercari’s Sports Business in January 2024. In that role I worked as an employee of Mercari, the Antlers’ sponsor, to devise marketing strategies that involved the team.

Sometime later, I started thinking about what Mercari could do to better serve the Antlers and pitched various ideas to leadership. Then, I volunteered to be seconded to Kashima Antlers and made the move in February 2025.

—Did you notice any major cultural differences between Mercari and Kashima Antlers?

Yes, definitely. One big difference is that Antlers members are always shaking hands. (laughs) On game days, team members exchange greetings and handshakes and pat each other on the back.

When working in an office, that level of physical communication is a bit of an alien concept. But it’s just what people do at the Antlers, and it’s an integral part of their communication style. Rather than relying solely on Slack messages, colleagues actually walk over to each other’s desks to have face-to-face conversations. That difference in physical communication was a breath of fresh air.

The secret weapon of the club: Mercari’s culture

—What approaches did you take to strengthen the management of the Antlers?

@hamagucci:  When the Antlers came out on top last year, it made me realize something—winning really improves the numbers. We sold more tickets and merchandise, and received more partnership inquiries. It became very clear that winning games translates to improved business performance.

Over the years, the team kept experimenting in pursuit of victory, but the results didn’t quite follow. So, the season before we won the championship, I told leadership that we had to invest in winning. But, of course, the company can’t make an investment without any sign of returns. So, I explored prospective areas that would eventually generate returns for Mercari.

I planned a series of “activations” aimed at enhancing the experience of fans at the stadium beyond simple brand exposure. We opened the Mercard Lounge and leveraged the Mercari Hallo service to offer food delivery in the stands.
One other topic that came up during these investment discussions was acquiring naming rights. Take uniform sponsorship, for example—it lets us reach people who watch the games on DAZN, but the audience is still limited. Securing naming rights meant that the name “Mercari Stadium” would appear on TV and in newspapers, as well as on local road signs. I suggested that this kind of exposure would be a significant return for Mercari, and we made it happen.

—So that’s how Mercari Stadium came to be. I heard that securing the naming rights also led to strengthening the Antlers’ roster. However, you must have faced some challenges as well?

@hamagucci:  A sports business is very different from a tech company, so there are structural challenges. At Mercari, employees experiment with new ideas in short bursts, but in soccer, the season runs as a single year-long cycle. Some months, the team plays only once. And because season tickets and other year-long commitments are in place, we can’t easily change things between games, as that could confuse our fans. So we often defer decisions until the following season.  But that’s not to say that one way of doing things is better than the other. What we are conscious of is how to effectively communicate the differences in pace to both sides.

Antlers’ passion sparks a fire at Mercari

—What are your takeaways after working directly with Antlers’ fans?

@hamagucci:  Some Antlers fans joined the fan club when they were children and have been members for over 30 years. I always try to remind myself of the history of the club and the passion of its fans.

The Mercari app processes millions of transactions every day, but we hardly ever get the chance to interact with users directly. Visiting the Mercari Stadium to watch the Antlers play and seeing 30,000 fans cheering left a big impression on me—the fervor from the crowd was incredibly powerful, even though the fans numbered much fewer than Mercari’s 23 million monthly active users. Being in the stadium, feeling that energy, and seeing how much the Antlers are loved and supported reminded me of just how much value that kind of passion holds.

—Expectations within the company also grew as we got closer to winning, right?

As we approached the end of the season, I was pleased to see that people were starting energized discussions before each game on our internal Slack channels about things like the starting lineup. And after the game, there were more posts praising certain players. It was great to see that people were enjoying both the game itself and also that pre-game and post-game sense of community.

What’s interesting is that Slack wasn’t very active during the final match, the reason being that everyone was at the stadium. (laughs) 

Partners who elevate each other

—Was there also a push for the Antlers to adopt Mercari’s values?

@hamagucci:  There was not much of a push to have the players and the team adopt our values directly. But, I think that’s actually a very positive thing—it means that the team already shared our core values. 

Kashima Antlers’ mission is “Everything for Victory,” which is almost exactly the same as our value “All for One.”  Despite being based in a small town and doubted as to whether they could compete at the top level, Kashima defied expectations. The town built a stadium, the club brought in Zico, and together they overcame challenge after challenge to become a powerhouse. I think that drive really embodies our “Go Bold” value. Also, the Antlers’ legacy exists because each generation has embraced “Be a Pro” in their own way.

Because Kashima Antlers and Mercari share these three values, we are able to move in the same direction without ever explicitly stating how to act based on those values.

—So, what does it mean for the Antlers to partner with Mercari, and what does Mercari gain from the partnership?

@hamagucci:  What makes the Antlers’ partnership with Mercari so effective is that Mercari is a company that values quick decision-making and drive. We act as both a parent company and a partner that helps the Antlers realize their goals.

People often say that the Antlers benefit from being able to access Mercari’s technology, but there is much more to the relationship than that. At its core, we are aligned on values, mission, and philosophy, and everyone believes that becoming J1 League and AFC Champions League champions is not just a goal, but an expectation. And now, because I can consult directly with Shintaro and Koizumi, decisions move very quickly. Being able to make speedy decisions and take on new challenges is a real strength.

On the other hand, what Mercari gains from the Antlers is their 33-year history, tradition, and brand. The team started from adversity and has since built a legacy, winning an unprecedented 21 J1 League titles. That history and brand reflect the belief that by holding onto high aspirations and putting in the work day after day, you can rise to amazing heights, almost like a miracle. I think that’s something the Antlers can leverage while sharing the same mindset as Mercari.

—How is it that Mercari and the Antlers help each other grow?

@hamagucci:  People often talk about how amazing the Antlers are, or say that they can achieve anything, but it’s important to remember that the team was not always at the top of their game. And, because we are based in Kashima, we still sometimes find it difficult to attract crowds compared to clubs in major cities. That’s why the team feels a constant sense of urgency—a fear that if they don’t keep challenging themselves, they will lose their edge and be left behind. This sense of urgency is something the Antlers and Mercari share; Mercari is always striving to stay at the forefront as trends continue to change.

So, I believe what we have in common is an unwavering drive, rooted in our cultures, to reach greater heights and set our sights on the world. The Antlers would never say, “We’re fine being in second place this year,” nor would Mercari say, “We don’t really care how many people use our app, just a few is enough.” It’s because we share the same high standards and aspirations that we can help each other grow.

—To wrap things up, please share your hopes for the upcoming season and your outlook for the future.

@hamagucci:  This year is set to be a historically irregular season for J1 League soccer. Even still, the team remains focused on winning the championship—our desire to win never wavers! 

Looking ahead, the first thing on the horizon is the new stadium. It would be interesting to use the stadium as a hub, bringing together partner companies from both sides, and even working toward building a world-class community that stands as a source of pride. Also, the team will play in the AFC Champions League this year for the first time in seven seasons. As the Antlers’ global presence grows, being recognized worldwide as part of Mercari Group will further highlight the value of having the Antlers within the Group.