Teenage boxer Callum Peters is into the men's middleweight quarter-finals in Birmingham but fellow Australians Kristy Harris and Billy Polkinghorn's campaigns are over.
Peters, on debut after a bye first-up, defeated Indian boxer Sumit on a unanimous points decision after fighting back from a difficult first round.
The 19-year-old will face Guyana's Desmond Amsterdam in Wednesday's quarter-final.
"Sumit was a really terrific opponent and I am so proud to have beaten him fair and square," Peters said.
"It was a war. It was thunder. I needed to get the job done and I did it. He was always there and that was a proper fight.
"I'm the youngest in the boxing team and the rest all really look after me. They helped me to dig deep into my soul and bring out the best in me."
Sumit came out firing from the opening bell, charging at Peters and unleashing a flurry of head and body blows, including cracking him with a right cross to the chin less than 40 seconds in.
The 19-year-old Indian landed plenty of rapid-fire combinations to Peters' body but the Australian grew into the round and landed some vicious left hooks.
Sumit won the first round unanimously 10-9 but was docked a point for careless use of the head, meaning the pair were locked at 9-9.
Peters seized control in the second round, with his left uppercut proving particularly dangerous as Sumit slowed down.
Peters worked over Sumit with his superior angles and movement in the third round to seal victory, with the Indian boxer twice given standing counts.
Meanwhile, Polkinghorn had hoped to emulate Harry Garside's 2018 gold medal triumph but lost his round-of-16 light welterweight bout to Uganda's Joshua Tukamuhebwa 4-1 on points.
Harris suffered a heartbreakingly close loss to Northern Ireland's Carly McNaul in the light flyweight round of 16, losing 3-2 on points.
