Gregor became acquainted with martial arts at the age of eight when he began training Shotokan karate. He became acquainted with kickboxing in 2001. A few years later, in 2004, he began competing in the Full Contact discipline, in which he still trains and competes today. Since 2014, he has been training at the Barada Sports Center, where he also works as a coach. As a professional, he achieved the titles: WAKO PRO European Champion -69.10 kg 2015, WAKO PRO European Champion -69.10 kg 2016, WAKO PRO European Champion -69.10 kg 2017 and WAKO PRO World Champion -71.80 kg 2019.