The 18-year-old home fighter, who last year competed at the Nanjing 2014 Summer Youth Olympic Games, as well as the International Boxing Association (AIBA) Youth World Boxing Championships and the EUBC European Youth Continental Championships, will meet Hungary’s Nandor Csoka for a place in the gold medal match.

Asenov’s fast hands saw him narrowly edge the first round exchanges against Sopinskiy before his stamina allowed him to take control of the contest in the remaining two rounds.

Csoka continued his dream tournament in Bulgaria, controlling his quarter-final with Belgium’s Dodji Ayigah to secure at least a bronze medal. 

"My first thoughts after winning my quarter-final was to think about my father, my mother and my whole family," said  Csoka.

"I began boxing only four years ago, and now I am a medallist in a European Championships.

"It is still hard to believe I will be there in the semi-finals.

"I believe only in hard training, and this is the result."

In the biggest surprise of the day, Russian National Championships silver medallist Adlan Abdurashidov, one of the gold medal favourites in the lightweight division, was outdone by Georgia’s Otar Eranosyan.

A second shock defeat for Russia came at super heavyweight as London 2012 Olympian and EUBC European Continental champion Magomed Omarov lost to Bulgaria’s Petar Belberov.

Four Russian athletes did qualify for the semi-finals, though, starting with light flyweight Vasilii Egorov, who defeated Spain’s Samuel Carmona Heredia.

Vitaliy Dunaytsev beat Moldova’s Dmitri Galagot at light welterweight, while there were also wins for World Series of Boxing supremo Petr Khamukov at middleweight and AIBA World Boxing Championships silver medallist Evgeny Tishchenko at heavyweight.

Elsewhere, Poland’s WSB star Tomasz Jablonski beat The Netherlands’ Max Van der Pas at middleweight, while Armenia’s Aram Avagyan overcame Romania’s Razvan Andreiana at bantamweight.

Spanish welterweight Youba Ndiaye Sissokho continued his impressive form with a win against Czech Republic's London 2012 Olympian Zdenek Chladek.

Croatia’s Hrvoje Sep defeated Bulgaria’s Radoslav Pantaleev in a closely-fought contest at light heavyweight, the same division in which Latvia’s Nikolajs Grisunins booked a semi-final place to ensure his country’s first European Championships medal since 2008.

Great Britain remain the most successful nation in Samokov, with six of their boxers in the semi-finals, including Nanjing 2014 Summer Youth Olympic Games bronze medallist Muhammad Ali in the flyweight division. 

As well as guaranteeing a medal, all the semi-finalists have also achieved a qualification quota for the AIBA World Boxing Championships in Doha. 

Following a rest day tomorrow, the EUBC European Confederation Continental Championships semi-finals are due to be held on Friday (August 14).


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