Promoter Eddie Hearn broke down in tears in paying tribute to American fighter Patrick Day, and said boxing must unite to make the sport safer.
Day died at the age of 27 on Wednesday, four days after suffering a brain injury in a 10th-round stoppage defeat by Charles Conwell in Chicago.
The bout took place on a bill promoted by Hearn's Matchroom Boxing USA.
After becoming upset, Hearn told IFL TV: "You can say 'it's boxing' but it is so hard to justify."
He added: "It has been a rough year for the sport. We need to make sure we get together as a community. We keep trying to evolve, we keep trying to make the sport safer.
"There are so many things we can look at as a community, particularly [brain] scans. One of the issues is the frequency of scans in my opinion. You can have a yearly scan but sometimes it doesn't take into account the fights you have had since that scan."
BBC Radio 5 Live Boxing's Steve Bunce and Mike Costello, and American boxer Regis Prograis have all had their say on how boxing can be made safer.
'Indefensible' boxing saves lives too
Day's is the fourth death in boxing in recent months, following the passing of Russian Maxim Dadashev, Argentina's Hugo Santillan and Bulgaria's Boris Stanchov.
Bunce said: "I have been ringside in the last 30 years for half a dozen deaths and maybe 12 or 15 other fights where boxers have been rushed to emergency procedures.
"I have been in waiting rooms, I've been there when doctors have told loved ones that their son, husband and father has died. I have been there when guys have been given no chance and pulled through after six or seven weeks in a coma.
"I have studied it. It's an odd business and I love it. It's what I do for a living but at the same time it is a sport that is indefensible. But, at the same time, boxing and boxers make perfect sense to me.
"I have wracked my brains to come up with anything that can make boxing safer. In Britain, the British Boxing Board of Control (BBBofC) has the world's finest safety measures yet we still have deaths. It is that simple. There is nothing that can be done.
"It's when you go and meet people at a gym in the worst part of a city and you take their testimony of how this sport has saved their life. That may sound like cliched rubbish, and I understand how it looks, but that is the bottom line.
"Unless you are in the business, you can't understand it. But I am not defending it, it is impossible to do so."