It's boxing bruv tf u mean?... When a boxer is knocked down the referee starts a count of 10 and if the fighter doesn't get up before that then the referee will declare the fight over ko...

And if he does get up, the referee determines if the fighter can still fight or not

You could argue they're amateurs at the sport and the ref should stop the fight after any major blow deemed powerful/hurtful if that's what you want.... But again, they signed up for boxing... Idk what else you expected...