Born in Nova Gradiška but hailing from the village of Podvrško, Mikanović started his youth career at the nearby NK Mladost Cernik.
He joined the U17 team of NK Osijek in 2009, spending the next three seasons there before moving to HNK Hajduk Split on a free transfer, as he was not offered a contract after he turned 18.
During his time with the club, Mikanović won 3 domestic cups and made 101 appearances in all competitions, scoring three goals and assisting eight.
[7] He made his league debut on 3 August 2024 in a home game against Varaždin, but was substituted in the 22 minute following an injury.
[8] Mikanović scored his first goal for the club on 30 August 2024 in the 76 minute in a 2–1 league win on home turf against the newly promoted Šibenik side.