Two years later, he joined OFK Beograd before moving abroad for the first time by signing for Lazio in Serie A, where he won the Coppa Italia and Supercoppa Italiana in 2009.

Making 27 league appearances in his debut season, the youngster left a good impression but could not help the beleaguered team avoid relegation.

[citation needed] In the summer of 2007, OFK Beograd sold Kolarov to Italian side Lazio (the third placed team in previous season's Serie A standings) for a €925,000 transfer fee.

[8] Kolarov's first goal for Lazio came at the Stadio Oreste Granillo in Reggio Calabria on 30 September 2007, as he hit a rocket from 38 metres to secure a draw against lowly Reggina.

[9] During his first season in Rome, the 21-year-old Serb also participated in the UEFA Champions League for the first time, making his debut on 24 October 2007 away at Werder Bremen in a 2–1 victory.

[citation needed] In his second season in Italy, Kolarov established himself as Lazio's first choice at left back, scoring a spectacular goal against Lecce at the Stadio Via del Mare.

With Lazio 3–2 up, Kolarov received the ball in defence from goalkeeper Fernando Muslera and proceeded to run the length of the pitch virtually unopposed.

[11] As the 2009–10 season drew to an end, Kolarov was instantly linked with a move away from Lazio, with Manchester City and Real Madrid supposedly interested.

[15] The summer 2011 arrival of Gaël Clichy to the club marginalized Kolarov's role in the squad and he saw his first team opportunities greatly reduced.

[16] On 1 October 2011, he started and played the full 90 minutes in the left-back slot against Blackburn Rovers at Ewood Park in a 0–4 away victory in the Premier League.

[citation needed] In June 2010, he was selected in Serbia's squad for the 2010 FIFA World Cup,[33] where he appeared in group stage matches against Ghana and Germany.

Despite not being gifted with significant pace, he was known for his overlapping attacking runs on the wing, as well as his passing, crossing, and powerful ball-striking ability with his left foot, and his accuracy from free kicks.

[42][43] Score and results list Serbia's goal tally first[19] On 3 June 2023, Kolarov was announced as the new sporting director of Italian Serie B club Pisa.