Dobrin debuted on the ISU Junior Grand Prix (JGP) series in September 2000. After winning silver medals in Ukraine and the Czech Republic, he qualified for the JGP Final in Ayr, Scotland, where he also took silver. After winning the Russian junior title, he was sent to the 2001 World Junior Championships in Sofia, Bulgaria. He placed 5th in his qualifying group, 20th in the short program, 12th in the free skate, and 12th overall.