While Vikash overcame a stiff challenge from Poland’s Dawid Michelus to reign by a 2-1 margin, Sumit upset ninth seeded Petru Ciobanu 2-1.
With the wins, both boxers are now just two wins away from a medal.
Meanwhile, Mandeep Jangra (69kg) faltered against Serdar Hudaberdiyev of Turkmenistan.
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