The 25-year-old flyweight was successful in the opening round in the 54kg division, beating Moldova's Yolia Korol by unanimous decision.

Petrova, who lost to Ukraine's Tetyana Kob in the round-of-16 at Rio 2016 in August, will be hoping for an extended run in front of her home fans.

The 54kg weight division does not feature England's back-to-back Olympic champion Nicola Adams, who is "having a break from full-time training" following Rio, with rumours that she is pondering turning professional.

Every bout on day one in the division in the Bulgarian capital was settled with all three judges agreeing.

Also successful was Romania's Lacramioara Perijoc, who got the verdict against Irishwoman Devla Duffy.

Snizhana Kholodkova of Ukraine was too strong for Szabina Szuch of Hungary while Russian Viktoriia Kuleshova was given the verdict against Italian Arianna Giulia Delaurenti. 

France's Delphine Mancini won 3-0 against Busenaz Cakiroglu of Turkey with Norway's Marielle Hansen getting the nod over England's Ramla Ali.

Two bouts were also contested at 75kg today, with England's Natasha Gale backed by two judges in her win over Sweden's Love Holgersson.

The third judge scored the contest as a draw.

In the second fight, Maily Nicar of France won by unanimous verdict over Ukraine's Mariya Borutsa.

One bout was also held on the first day in both the 51kg and 60kg divisions.

In the lighter class, Katrin Noren of Sweden gained the backing of all three judges against Hungary's Krisztina Beri.

At 60kg, Esra Yildiz won for Turkey, 3-0 over Italian Sara Corazza. 

Action will continue in Sofia tomorrow with more opening round bouts.