Eventually, he made his professional debut for Ried on 11 May 2014 in the last match of the 2013–14 season, a 2–5 home defeat against Rapid Vienna, where he played 89 minutes.

A few days later, first-team coach Pep Guardiola added him to the squad for the first leg of the 2014–15 UEFA Champions League quarterfinal against FC Porto.

[7] Lučić made his Bristol City debut in a 2–1 EFL Cup win against Fulham on 21 September 2016, a game in which he saved a Cauley Woodrow penalty.

[11] Lučić made his international debut for the Austria national youth football team in an under-16 match against Hungary at Bruck an der Leitha on 28 September 2010.

Lučić then debuted for the Austrian under-19 side against Northern Ireland at Vienna on 11 September 2013 and was subsequently added to the squad for the 2014 UEFA European Under-19 Championship, where he played in two group stage matches against Hungary and Israel and in the semifinal against Germany.