Team Ireland made a good start at the Olympic boxing qualifiers in London with Emmet Brennan, George Bates and Afanasev Kirill all advancing to the last 16.
But there was disappointment for Christina Desmond, who was beaten by second-seed Angela Carina in the welterweight division.
The referee stopped Brennan's light heavyweight bout with Bosnia and Herzegovina's Radenko Tomic in the second round.
The Dubliner will face Uke Smajli of Switerzerland in the last-16 on Tuesday, needing a top-six finish to qualify for Tokyo.
"I stuck to instructions and it just went a little bit better than we thought," he said afterwards.
"The plan is to go all the way, you don’t come here without planning on that."
🥊 RESULT 🥊
— IABA (@IABABOXING) March 15, 2020
The perfect start to the tournament for Team Ireland as Dublin's Emmet Brennan gets a stoppage win v 🇧🇦!
He has now booked his place in the Last 16 v 🇨🇭 on St.Patricks Day!
Well done Emmet!🥊🇮🇪#IABA #RoadToTokyo2020 pic.twitter.com/buGxRveIgY
George Bates beat Leon Dominguez Becerra on points in the lightweight section after their fight was stopped in the first round.
The referee stopped the fight with 29 seconds remaining after Becerra suffered a bad cut above his eye following a clash of heads, with the doctor deeming the Spaniard unable to continue.
Bates will be back in action on St Patrick's Day.
"I'm very satisfied with the performance," said the Irish champion. "It all went well from the start. I’m planning to go all the way."
Desmond fell to a tough defeat, however. The Cork fighter suffered a unanimous defeat against Carina, with all five judges awarding the bout to the Italian.
Ireland ended the night on a winning note when Afanasev won a tight contest against Georgia's Begadze Nikoloz.
The Dublin heavyweight edged a hard-hitting first round where both fighters went on the offensive, but Afanasev finished strongly with a stiff right hand to gain favour on the scorecards.
Nikoloz came back strongly to take the second round but Afanasev responded impressively in the third to take a majority 4-1 decision.
There are five Irish fighters in action on Monday. Welterweight Aidan Walsh faces Pavel Kamanin of Spain while Michael Nevin takes on Dutch boxer Pas der Van at middleweight in last-32 bouts.
Brendan Irvine fights Istavan Szaka for a place in the men's flyweight quarter-finals, with women’s flyweight Carly McNaul up against Britain’s Charley Davison.
Kurt Walker faces German Hamsat Shadolov in the last-16 of the featherweight division.
Monday's bouts at the Copper Box will continue behind closed doors due to the coronavirus outbreak.
