During the 1976–77 season, Marek defeated CSKA twice, home and away, with the scores 2:1 and 3:1. That season, the club led the league for several rounds and at the end the team fought tooth and nail with Slavia Sofia for the third place in the table. Marek won the decisive game against Slavia in Dupnitsa by the score of 1:0, finishing 3rd and earning an entry into the 1977–78 UEFA Cup. This is Marek's best finish to date in the top flight of Bulgarian football.