Litex sack coach Chervenkov
Litex, who won their third league title last season, lost to Slovakian champions Zilina 4-2 on aggregate in the third qualifying round.
"We're disappointed because we missed a golden chance to take part in the Champions League's play-offs," Litex said in a statement, adding the club and Chervenkov will part with immediate effect.
Chervenkov took charge of the Lovech-based side last September, replacing Bulgaria coach Stanimir Stoilov, who resigned following an early European exit.
Youth team coach Petko Petkov was named as Chervenkov's replacement.