“I started training in the martial art of Judo at the age of five, and trained traditional Japanese Jiu-Jitsu for ten years, earning the rank of black belt before I met Mike Yanez,” Daniël Bertina, a Dutch native who lived in Louisville at the time, says.

“I have trained under many inspirational and excellent coaches in my life. That being said, I have never met another person who such a genius at making fighters out of ‘average joes’. Yanez instilled a ‘never-die’ willpower in his students, and the way he taught our small group of students how to master the basics, and how to grow in the art was remarkable. He took me from a hyperactive and spastic Japanese-style leglocker to a well-rounded Brazilian Jiu-Jitsu blue belt. I still use and teach his basic approaches and concepts to my own students.”

Daniël Bertina (who was nicknamed "Amsterdam" during his stay in the US) is currenty an assistant instructor and brown belt in BJJ under Marcos Flexa of Carlson Gracie Holland, based in Amsterdam. Although fiercely loyal to the Carlson Gracie Team, he still considers himself a proud member of Team Popovitch.