Saweety stunned 2018 World Champion Wang Lina of China 4-3 after bout review. Nitu (48kg) made lightwork of the two-time Asian bronze medallist Lutsaikhan Altantsetseg of Kazakhstan to secure a remarkable 5-0 win by unanimous decision.
The biennial event will also see a massive prize pool of Rs 20 crore as the boxers will compete in 12 weight categories.
The 19-year-old pugilist, who was making her maiden appearance in the World Championships, lost the gold medal bout 1-4 against second-seeded Ekaterina Paltceva of Russia.
Manju has assured herself of at least a silver medal as she dominated her bout against her Thai opponent and registered a 4-1 win in the semi-final stage of the competition.
Mary dominated much of the bout with her punches being more accurate than her opponent on a consistent basis.
She will next face Algerian fifth seed and defending champion Ouidad Sfouh in the pre-quarterfinals in what will be a tricky bout for her.
