CSKA Sofia have sacked coach Miodrag Yesic and replaced him with Plamen Markov.
CSKA, the reigning Bulgarian champions, have struggled since the resumption of the league, winning just one of their last four games.
A 1-0 defeat to Levski Sofia on Sunday left them three points adrift of their city rivals.
Yesic took over from Ferario Spasov in February 2005.
Markov, who led Bulgaria at the 2004 European championship in Portugal, has signed a two-year deal running until June 30 2008.
Subscribe to World Soccer – The essential football magazine.