Bulgarian Cup favourites CSKA Sofia and bitter city rivals Levski were knocked out in the quarter-finals on Thursday.
Holders CSKA suffered a shock 2-1 defeat at second division Septemvri Simitli and only managed a late consolation goal from their Cameroon midfielder Njongo Priso two minutes from time.
"I'm the happiest man on earth," Septemvri coach Stefan Goshev told reporters. "The lads will not receive a single lev for the win but the memories will last forever."
Levski, who have won the cup 25 times, were dumped out in a 2-1 extra-time loss at Lokomotiv Plovdiv who equalised in added time at the end of 90 minutes through defender Mihail Venkov.
Referee Ivaylo Stoyanov sent off Lokomotiv's Basile de Carvalho and Levski's Hristo Yovov and Cristovao Ramos as well as showing nine yellow cards in a tense affair.
On Wednesday, champions Litex Lovech and surprise league leaders Ludogorets reached the semi-finals.comments