He got lucky.. he knew the dangers of boxing and the sport basically let him beta test the bad side of it. Time to retire.
In Japan there are many tragedies in boxing this last past years... I'm sure Jin Sasaki can be a world champion with a better defense and a fight for a vacant belt because Ennis moved up in Super Welterweight. But also my spirit says that even he is young only 23 he probably should retired. This knockout was very brutal... The behavior of Brian Norman Jr. and his father was also very disrespectful.
With Jin Sasaki I seriously think Luis Alberto Lopez, Manny Pacquiao, Deontay Wilder, Tony Yoka, Miguel Berchelt, Satoshi Shimizu should probably be retired at the same time too... It's dangerous for them to continue to do this sport. The difficulty is that they know that some boxers continues at a old age and are still pretty good like a good vine : Nonito Donaire, Phai Pharob, Luis Ortiz, Zhilei Zhang, Kubrat Pulev, Erislandy Lara, Wlodarczyk, Kovalev... And this fact with probably the money retained them I think.