Former national boxing champion Duryodhan Singh Negi tested positive for COVID-19 and has been hospitalised as a precautionary measure despite being asymptomatic, the Sports Authority of India (SAI) said.
Competing in his maiden world championship, Negi, a former national champion, lost 1-4 to the sixth seed.
Four-time Asian medallist Shiva Thapa became India's first gold-medallist at the President's Cup boxing tournament after getting a walkover in the final.
Gaurav Solanki (57kg), Prayag Chouhan (75kg) and Brijesh Yadav (81kg) tested positive for the virus
Zareen won the bout after local favourite and former champion Sevda Asenova abandoned the contest during the opening round.
Summary of sports events and persons who made news on Sunday
Summary of sports events and persons who made news on Tuesday
A summary of sports events and sports persons, who made news on Saturday
Nikhat from Telengana was handed the fourth spot in the 51 kg category which already has the six-time World Champion MC Mary Kom, RSPB's Jyoti Gulia and Haryana's Ritu Grewal as other contenders.
The new season begins on Star Plus from April 26.