Though briefly a member of the Greece national team, he decided to pursue tennis seriously at age 20 while studying sport science at the University of Athens.

[4] As Stefanos began to find success as a junior, Tsitsipas left a high school teaching position to travel with his son full-time from age 11 or 12.

[12][13][14][15] In the 2022 Australian Open semifinals, Tsitsipas's coaching spurred Daniil Medvedev to exclaim to the umpire, "His father can talk every point?

", and prompted officials to place Greek umpire Eva Asderaki-Moore near the player's box to overhear his chatter, leading to a fine.

[12][16][17] Tennis commentator Jim Courier suggested after a Stefanos Tsitsipas loss in November 2022 that his father's coaching style during matches "[is] hurting him more than it's helping".