Jiri Prochazka was a football hooligan in his native Czech Republic until martial arts and an ancient Japanese text inspired him to turn from street fighting to cage fighting -- and become a UFC world champion.

"The Book of Five Rings" was written in 1645 by the master Japanese swordsman Miyamoto Musashi, and when Prochazka was handed a copy about eight years ago he finally found the focus to "become a warrior" after a wildly misspent youth.

"You have to look into yourself, and you have to follow the rules -- be honest, be brave, be calm in hard situations," said the 29-year-old Prochazka, of what he has learned from the book and from the "Bushido" Samurai code of discipline that it encourages.

Prochazka became the UFC's first Czech world champion after a thrilling back-and-forth battle with Brazilian light heavyweight Glover Teixeira that went deep into the fifth and final round in Singapore in June.

A battered Prochazka seemed on the verge of defeat to Teixeira, but somehow drew on reserves of strength to apply a choke hold and force the Brazilian veteran into submission.

"Some people say my style is unpredictable," Prochazka told AFP.

"But I'm not doing unpredictable things. I am calm and I just look for the space for attack -- where is the weak point of my opponent -- and I attack."

- Spartan surroundings -
Prochazka was speaking via video phone call from a remote cottage in a forest retreat 30 minutes drive away from his birthplace in the southern Czech city of Brno.

His spartan surroundings, Prochazka explained, are so he can be alone with his training. The cottage has electricity but no running water, forcing Prochazka to take daily trips to a well.

Prochazka pointed his phone outside the cottage to show the Dojo, or fight ring, he has carved out of the forest floor and the gym equipment frames he has fashioned from local timber.

"You have to find the way that is best for you and this is what's best for me," said Prochazka, whose hair is styled in the "chonmage" top-knot favoured by Japan's ancient Samurai warriors.

"I meditate, and I train, and I live the life I want to be living."

- 'Never stop learning' -
The sense of calm and purpose wasn't always with Prochazka.

As a teenager he fell in with the local Ultras -- football hooligan gangs -- supporting FC Zbrojovka Brno and fought in more than 100 street battles with rival fans.

"It was a part of my life and without that there would be no me like I am today," said Prochazka of his youth. "I had to be that guy to become the guy I am now."

At 17, Prochazka discovered Muay Thai kickboxing at a local gym and that he could fight legally.

After winning a national title at 19 he turned to MMA as the sport began to grow in global popularity.

Prochazka's talent led him to Japan with the Rizin Fighting Federation where he was advised by a coach to read Musashi and the history of the ways of the Samurai.

Prochazka started winning in Japan and his life turned around. A Rizin MMA title was followed by a call from the Las Vegas-based Ultimate Fighting Championship in 2020.

Two straight knockout wins gave him the chance to face the 42-year-old Teixeira for the world title at UFC 275 in Singapore and Prochazka grabbed it.

Back in his cottage, recovering from a knuckle break suffered against Teixeira, Prochazka was plotting the next phase of his career and a possible rematch with the Brazilian and.

"I am still going forward," said Prochazka.

"In our lives we all have to fight at some time, in different ways. So I am still learning and I think we should never stop learning."