Boxing governing body AIBA removed headgears at events since 2013, including two world championships and one Commonwealth Games
On debut day for Olympic boxing, fighters said they were happy to be competing at the first Games since 1980 without protective headgear, welcoming better peripheral vision even if it means more cuts and scrapes.
After decades of debate, and some studies suggesting headgear did not make the sport safer, boxing governing body AIBA eliminated the equipment at events since 2013, including two world championships and one Commonwealth Games.
With a global audience at the Olympics, boxers said they were especially pleased to go - even if no headgear means more scratches and, sometimes, cuts.
"You feel unimpeded," said Juan Nogueira, a Brazilian heavyweight from São Paulo, the biggest city of the host country, whose fans erupted in cheers as he defeated Australian Jason Eric Whateley on Saturday.
"He is a really good opponent, a technical fighter, and I was happy to be able to see more," he added, echoing comments by other fighters that headgear limits a boxer's ability to see to the side.
The prospect of cuts, and consequent stopping of matches because of safety concerns about blood, continues to be a sore subject. At the Commonwealth Games in 2014, Australian Daniel Lewis complained that he lost a medal because he was deemed unfit to compete because of a cut.
Still, on Saturday most boxers said they were willing to take the risk.
"Yeah, you can feel the sting a little more, but it's worth it," said Misael Uziel Rodriguez, a Mexican middleweight who squares off against Iraq's Abdulridha Waheed on Tuesday.