 On 8 June 2005, Kruglov signed a five-year contract with Russian Premier League club Lokomotiv Moscow.He made his debut in the Russian Premier League on 3 July 2005, in a 4–0 home victory over Terek Grozny.In July 2006, Kruglov joined Russian First Division club Kuban Krasnodar on loan until the end of the season, making just one appearance in the Russian Cup.