A goalkeeper born in Belgrade in 1996, he grew up in his hometown club FK Rad. At only 17 years of age, he made his debut in the first team, collecting 22 appearances in the Serbian top league.

In summer 2015 he was bought by Atalanta, with whom he made his Serie A debut on 15 May 2016, in the away win against Genoa (1-2). He played on loan at Avellino in the 2016-17 season, then with Salernitana and Cremonese: in three years he totalled 76 matches in the cadet tournament. He returns to Serie A with Hellas Verona in the 2019-20 season, before moving back to the ranks of Atalanta last season. He arrived at Cagliari in July 2021, during his first season he made his Serie A debut at San Siro against AC Milan on 29/8. He became the true star of the red and blue team in the 2022-23 season in Serie B with 43 appearances and 16 clean sheets. He contributed to the promotion to Serie A through some sensational interventions and thanks to the confidence he transmitted to his rearguard.

In his career he has 18 matches with the U21 national team.

Strong in high catches and exits, where he can exploit his powerful physique (he is 1.94 m tall), despite his size Radunović is characterised by his responsiveness, and is also good at ground interventions and low saves.