Career
He is a 1.90 m tall combo guard who currently plays for PAOK of the Greek Basket League. In his pro career, Duvnjak has played with the following clubs: Partizan, Sloga Kraljevo, Atlas Belgrade, Vojvodina Srbijagas, FMP Železnik, Radnički Knight of the Order of the Garter 06, PBG Poznań Basket, New Yorker Phantoms Braunschweig, Mega Vizura, PAOK Thessaloniki, Rethymno, Panionios, and AENK. In 2015, he signed with PAOK.
He played at the 2004 International Basketball Federation Europe Under-18 Championship, and at the 2007 World University Games.