During a league fixture against FK Zeta on 21 March 2006, he suffered a double open-fracture of both his tibia and fibula following a challenge by Jovan Markoski in the 6th minute of the match.

Following the first operation at Belgrade's VMA clinic, the prognosis was 6–8 months away from the pitch, however, due to slow recovery another surgery was required.

This one took place in early January 2007 at the Orthopedic clinic in Belgrade As his contract with Partizan expired during his rehab, on 4 September 2008 Partizan management led by general-secretary Gordan Petrić and football director Ivan Tomić decided to extend Brnović's contract until summer 2009.

Two years later he moved to Iranian Mes Sarcheshmeh, where he spent six months during which he played 18 games and scored three goals.

Brnović made his debut for FR Yugoslavia (later, Serbia and Montenegro) in an April 2002 friendly match against Lithuania and earned a total of 16 caps, scoring no goals.