During the 2002–03 JPG season, Dobrin was awarded gold at both of his assignments – Chemnitz, Germany and Milan, Italy – and silver at the JGP Final in The Hague, Netherlands.

He won silver at the Russian Junior Championships and gold at the 2003 European Youth Olympic Festival in Bled, Slovenia.

He finished 5th at the 2003 World Junior Championships in Ostrava, Czech Republic, after ranking fourth in his qualifying group, second in the short, and sixth in the free.

In early March 2005, Dobrin won the bronze medal at the World Junior Championships in Kitchener, Ontario, Canada.

After placing 7th at the 2005 Trophée Éric Bompard and 10th at the 2005 Cup of Russia, he won his first senior national medal, bronze, at the 2006 Russian Championships.

Competing in the Grand Prix series, he won bronze at the 2006 Trophée Éric Bompard and placed 8th at the 2006 Cup of Russia.