He reminds me of another eastern European fighter, Leonard Dorin, very similar case :
- Alexandr Gvozdyk : 5 years of pro after a brilliant amateur career, one gold medal at Summer Universiade and one bronze medal at Olimpics, WBC champ as a pro, retired at 33 years old after the first loss, by TKO, against Arthur Berbetiev.
- Leonard Dorin : two bronze medals at Olimpics, one gold at World Amateur Championship and one gold at European Amateur Championship, turn pro at 28 years old, WBA champ, retired at 34 after his first loss, by KO, against Arturo Gatti.