In spring 1992, with the outbreak of the Bosnian War, he fled his hometown by being sent to Belgrade along with his sister while their parents joined them several months later.
In 1993, disappointed with being demoted to FK Rad's second team, the youngster switched to basketball by starting to attend KK Partizan-organized training sessions administered by the youth coach Dragiša Stamenković at the France Prešern Elementary School in the Belgrade neighbourhood of Miljakovac.
Deemed talented enough, Ćapin was attached to KK Partizan's youth system where he was coached by Stamenković for a few seasons before progressing up the age groups within the system and being coached by Igor Kokoškov, Milovan "Kime" Bogojević, Aleksandar Bućan, and Nenad Trajković.
[1] Among the fellow prospects Ćapin shared rosters with at Partizan youth system were Marko Peković, Vule Avdalović, Aleksandar Gajić, and Mirko Kovač.
He arrived at the club via attending a club-organized summer junior camp where Krka wanted to identify and potentially sign new young players.
[1] In his debut season as a professional, Ćapin saw some playing time in SuproLeague as the third option at the point-guard position behind Simon Petrov and Dražen Anzulović on a squad that also featured shooting guard / small forward Saša Dončić, center Bennett Davison, veteran center Franjo Arapović, and power forward Dragiša Drobnjak.
Between 2004 and 2008, Ćapin played for Gravelines-Dunkerque in France, for Panellinios and Panionios in Greece, and for Viola Reggio Calabria and Cimberio Varese in Italy.