Caroline Dubois moved a step closer to her dream of qualifying for the Olympic Games as she won her first ever senior bout at the Olympic qualifying tournament in London, but there was a shock for Delfine Persoon, who is out.

While the sporting world was shutting up shop, things continued at the European Olympic Qualifying event at the Copper Box in London. With more than 300 boxers from 43 nations having been in the city for more than a week, the decision was made to press on with the tournament.

Dubois, the 19-year-old sister of unbeaten heavyweight Daniel Dubois, was the very first boxer in Ring A, facing Ala Staradub, of Belarus, and ran out a unanimous points winner.

At junior level, Dubois won world, European and Youth Olympics gold medals, but her lack of senior experience meant she was unseeded here. She boxed well for the first two rounds, beating Staradub to the punch, but started to look tired in the final round.

“This is the first fight which is always the worst one,” Dubois said. “It was OK, not my best, and if you ask any of the coaches, they’ll tell you that. I can be much better.”

Next up is a bout against the No 1 seed, Mira Potkonen, of Finland, who is more than twice her age and who beat Katie Taylor on the way to a bronze medal at the 2016 Olympics in Rio de Janeiro.

“You’ve got to beat the best,” Dubois said. “She is obviously a top seed but at the end of the day she only has two hands, two legs and one brain and that’s the same as I have.

 “I know exactly what to expect and she knows exactly what to expect of me.  It’s going to be a good fight for sure.

 “There is no pressure being from London. I don’t even think about that.  If anyone has pressure, it’s Mira Potkonen.  How is she going to feel getting into the ring with a 19-year-old, in her mind she will be thinking that she can’t lose to someone my age.”

A big shock came in the bout straight after Dubois in Ring A as Persoon, who reigned for five years as WBC lightweight champion before losing a controversial decision to Taylor at Madison Square Garden last year, was beaten on points by Nikoleta Pita, an unsung 22-year-old from Greece.

Persoon made the classic mistake of professionals reverting to the amateurs and started too slowly. Pita rushed her in the first and by the time Persoon started to find her range, she was already two rounds down. She landed several hard shots in the third round, but she could not force a stoppage or a count. She looked shocked as the verdict was announced an blanked reporters as she walked through the mixed zone.

On a busy first day of action, one of the most impressive performances came from Ukrainian super-heavyweight Tsotne Rogava, who dropped Algirdas Baniulis, of Lithuania, twice on the way to a clear points decision.

Those in attendance were denied the big super-heavyweight clash of the evening when Clemente Russo, the two-time Olympic silver-medal from Italy, withdrew from his clash with Britain’s Frazer Clarke at the last minute. The official reason was given as an abdominal problem, although his coach suggested it was an upset stomach.

Clarke moves on to a clash with the tournament’s No 2 seed, Marko Milun, of Croatia.

Day 2 sees 50 bouts scheduled, with sessions starting at noon and 6pm (GMT). All bouts will be screened live on olympicchannel.com.