Born in Trebinje, SR Bosnia and Herzegovina, SFR Yugoslavia before the country's break-up, Gaćinović played in the Yugoslav Second League mostly with FK Leotar, but also a half-season with GOŠK-Jug.
In 2015 he accepted a call from major Lithuanian A Lyga side, FK Sūduva, which he coached in seasons 2015 and 2016.
[4] Afterwards, he returned to Serbia and worked as the assistant manager at Serbian SuperLiga clubs Vojvodina and Spartak Subotica.
[4] Gaćinović led the team to an historical upset elimination of Sparta Prague in the second qualifying round for the 2018–19 UEFA Europa League.
[7] On 6 June 2019, it was announced that Gačinović will once again be taking over the Spartak Subotica managerial position.