Born on February 10th in Zambok, Croatia, Kotarski joined the academy of local club Todah Bedekovcina from the age of six. It was not long before he impressed Dinamo Zagreb and in 2011 he moved to the capital club.

His performances did not go unnoticed by Ajax, who secured his signature in July 2017, before he even turned 18. As soon as he became an adult he took the plane to Amsterdam and became Ajax’s third-choice goalkeeper.

He played in the second team, making 60 appearances, and in the summer of 2021 he returned to his homeland with Gorica. In 28 games, Kotarski had eight clean sheets, while at the same time he established him self in the Croatia Under-21 side, having passed through all of the youth age levels before that.

The departure of Alexandros Paschalakis opened a place between the posts at the club, with Kotarski being the man selected to fill that void.

PAOK and Gorica came to an agreement and the Croatian ‘keeper is now a resident of Thessaloniki for the next four years.