Prior to the 2018–19 season, Tanasković was loaned out to Mladost Zemun as a two-way affiliate player, making him available for the senior roster of Partizan.

On December 22, 2018, Tanasković made his Adriatic League debut with Partizan in a home win over Cedevita, making no records in under 3 minutes of playing time.

[1] On February 5, 2019, at age 17, he debuted in the EuroCup in a loss to Alba Berlin, recording 6 points and 2 rebounds in under 11 minutes of playing time.

In June 2022, Tanasković signed a 3-year contract with Igokea of the ABA League, joining his brother's team.

[5] Tanasković was a member of the Serbian under-16 national team that won the bronze medal at the 2017 FIBA Europe Under-16 Championship in Montenegro.