In 2010 the starlet was spotted by the Latvian Higher League newcomers FK Jelgava, as they signed a contract with him before the start of the season.
[2] He managed to win the Latvian Cup, as well as made a margin in FK Jelgava history in a friendly match against Blackpool as the first player to score a goal against a club from the Premier League, as well as the first player to score a goal in the club's new stadium – Zemgales Olimpiskais Sporta Centrs.
[6] Before the start of the 2014 Latvian Higher League, on 19 January, Kozlovs made an official return to his former club FK Jelgava.
Filling the vacant forward's place in the first eleven he quickly made an impact as Jelgava managed to reach the bronze medals of the Latvian championship for the first time in the club's history.
With 15 goals in 34 matches Kozlovs became the third best scorer of the championship behind the Skonto FC forward Vladislavs Gutkovskis and FK Liepāja midfielder Jānis Ikaunieks.
[10] Kozlovs made his debut for Latvia in a friendly match against China on 17 November 2010, coming on as a substitute in the 76th minute.