The Indian defeated Venezuela's Karlha Magliocco 3-0 in the quarterfinal bout of the event, where boxers have been individually invited by the world body and the Rio Olympics organising committee.
Mary Kom, 33, will next be up against Virginia Fuchs in the semifinal bout tomorrow.
The five-time world champion had been laid low by a shoulder injury which forced her to skip last year's World Championships.
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The Team travelling to Serbia:
Sarjubala Devi (48kg), Neeraja (51kg), Y Sandhyarani (54kg), Soniya (57kg), Priyanka Chaudhary (60kg), Simranjit Kaur (64kg), Kavita Goyat (75kg), Saweety Boora (81kg), Seema Punia (82kg).
