He made his official debut in top division of Bulgarian football as a 17-year-old in a match against Lokomotiv Sofia on 29 November 2003.

On 6 February 2010, CSKA Sofia sold Timonov to Russian Anzhi Makhachkala for a reported transfer fee of $500,000.

On 20 March 2010, he made his official debut for his new team in the 0:1 away loss against Amkar Perm in a Russian Premier League game after coming on as a substitute for Nicolae Josan in the 84th minute of the match.

On 6 November 2010, he was giving a half-time interview to a sideline reporter during a league game on live TV and said "If we score a penalty, everything will be fucking great."

Anzhi manager Gadzhi Gadzhiev said that Timonov probably didn't quite know that what he was saying was a swear word, but he will be fined by the club for the incident nevertheless.