He started training Muay Thai when he was 14 years old, under the guidance of former world champion Gilbert Ballantine, Hans Nijman, Dick Vrij.
[3] Douwes made his breakthrough at the K-1 World GP 2008 in Amsterdam when he knocked out James McSweeney in the first round and entered the tournament as the reserve fighter after Freddy Kemayo had to pull out due to an injury.
[citation needed] On 28 February 2015 at Differ Ariake in Tokyo, Japan Douwes participated in the first hybrid MMA tournament called Ganryujima and broadcast on Fuji 1 Sports.
He represented kickboxing alongside eight men from different fight styles: Judo, Karate, Capoeira, Senegalese Wrestling, Sumo, MMA, Shuai Jiao, and Combat Sambo.
Douwes won the tournament, defeating Kamen Georgiev (Combat Sambo), Han Wula (MMA/Shuai Jiao) and Amaramend Boldo (MMA/Sumo), all by first-round KO.