The central defender, who won the competition with his El Barrio team, talks about his experience from the inside...
Martin, you've played at the Camp Nou before with Leganés...
"Never in such an atmosphere. When I came with Lega, there were about 70,000 people, it was obviously not full like Sunday, really nothing to do with the two."
A week after El Clásico, the Kings League offered an unprecedented spectacle that the public enjoyed.
"It was a real success on all levels: atmosphere, sound, and (everything else). The people had a great time and, it's important to note, there wasn't a single insult, violent gesture or anything like that. It was nice to see that from the pitch, a real party atmosphere."
For many people, it was their first time at Camp Nou. Can this kind of event reassure parents who are sometimes afraid to bring their children to a match?
"It's true that it was a different audience, a young audience, and that helped bring a new (reception) to the stadium. What stands out for me is that even people from Barcelona had never been to Camp Nou before, (but) they did for the Kings League. That speaks for itself and it also explains the magnitude (of it). It was spectacular and very well done."
How did you get involved in this adventure?
"I was contacted once and had to decline because I live in Madrid. I discussed it again afterwards, the conversation went very well with Adri Contreras, the president of El Barrio, and after I got interested in the Kings League, I decided to go for it. I'm delighted with the experience, it was great fun. We made it to the top eight and then qualified to play at Camp Nou."
Have you scored a brace in your career before?
"Yes, once with Huesca in La Liga (his last game in La Liga (against Leganés!)). But about my second goal on Sunday night - many of my striker friends sent me messages of congratulations, not only for the MVP award in the final but for the way I scored (laughs). It was not an easy situation, especially for me who wasn't used to being up (in front of goal)."
Obviously, given the number of brands involved and the huge success, one wonders if you are paid for the Kings League?
"We are paid for the journey and all the players receive the same salary, which is 75 euros gross. That's it. It will be a compulsory development for the Kings League anyway, because the players are the players and because a lot of money is generated around the competition. It's inevitable because of the size of it. It was a new format and everything was clear and transparent from the start."
Will you be present for the second season?
"I don't know yet because it will be the summer, there's the family, the holidays. I obviously want to continue with this team and these partners."
El Barrio has claimed to be the humble team of the Kings League. Given your career, especially as captain of Leganés, that must have spoken to you...
"Absolutely, I was convinced by the notion of a working-class neighbourhood and humility. It has animated us. We are happy, especially for Adri, a very good guy, approachable and whose personality was reflected in the way we played. We formed a strong and hard-working group, which allowed us to be consistent and win the tournament."
On Saturday in a press conference, Gerard Piqué decided to change a rule by allowing the referee to penalise a refusal to attack. It was aimed at El Barrio, who looked a bit like a 'cholista' team but won the final 3-0...
"In my opinion, we were the most consistent team, both individually and collectively. On the eve of the final four, there was indeed this new rule which in the end did not impact us. We took it as an incident."
We were able to meet José Juan in the stadium after your victory. He beat Real Madrid in the Copa del Rey with Alcoyano, he was emotional, but it felt like the Kings League was as important as a trophy in 11-a-side football. Thoughts?
"I think there will be a before and after final four because something has happened, and it's here to stay. The Kings League showed the arrival of a new format, a different model. On a personal level, and it's the same for José Juan, who is living his last years as a player, it was a good way to continue the pleasure, to show ourselves in front of many people, to play in front of so many people. It was very rewarding."
You are 38 and have children - did you know the streamers as well as they did, or was it a totally foreign world to you until then?
"I had to get to know everyone a little bit, that's for sure! But my eldest daughter, who is nine, was following several, she knew who was who. When I showed her who I was with through the Kings League, she couldn't believe it! I understood what the streamers and YouTubers could represent for this generation. And for me to be able to play in front of so many people, in such a stadium, in front of my wife and kids, it was great because they hadn't been able to see this kind of event for a while."
One very surprising aspect was that it lasted almost eight hours, not including the bus reception, and that this generation accused of not knowing how to concentrate stayed in the stadium en masse...
"It was a real show, a great show and it was fluid, between the presidents' talks, the matches, the concert, the hip-hop battle. There was no boredom, whereas in a classic football match you can get bored. It was both exciting and digestible."
The notable difference in this clash of generations was that David Villa was not the most expected guest star but rather influencers!
"It was a totally different world (laughs). But this new world is already here and on Sunday it really showed its passion. It was quite reassuring to see more than 92,000 people in a stadium to watch football, people who left delighted with what they saw, especially as the atmosphere was ideal for children. It was a great experience for everyone."