Calm has returned to the streets of Pretoria following a chaotic march against immigrants on Friday..
The retired boxing legend is a huge admirer of the 24-year-old singer - who was arrested for assault after allegedly punching a man on Sunday (27.10.13) - but believes he needs to get his temper under control.
Mike said: ''I really like and admire that little guy but what he really needs to understand is that eventually, if you keep doing that stuff, people will turn on you.
''I'm just worried about him, because he's really a sweet kid. He's probably going through some overbearing pressures and if he keeps getting violent - he was arrested for this, assault here, assault there - they're going to put him somewhere where that's all they do, assault people.''
The 47-year-old sportsman has plenty of experience with anger issues as he was rather volatile in his heyday, once biting off part of opponent Evander Holyfield's ear during a boxing match.
However, Mike has changed his ways since then and feels the 'Forever' singer should do the same.
In an interview with US radio station 95.5 WPLJ, he added: ''He's got to get it together. I can't even believe I'm saying this because I've [been through bad situations]. If you're not humble in this world, this world will thrust humbleness upon you.''
Chris was released without bail from a police station in Washington, DC, on Monday (28.10.13).
He was in custody for allegedly assaulting a man during a late night altercation outside the W Hotel.