Wanderers boss Dougie Freedman revealed he was in talks with the Barcelona-based team earlier this week and those talks have reached a successful conclusion.
The terms of the 33-year-old's transfer are undisclosed at present.
Petrov has a history in Spain, having featured for Atletico Madrid before his move to Manchester City in 2007.
But despite a regular role in previous seasons, Petrov failed to nail down a starting berth in 2012-13 despite scoring three goals in 16 appearances.


 





