EXCLUSIVEIt all went down back in March when P was coaching his team, The P Miller Ballers at a tournament at a high school gym in Tennessee.
It's unclear what started the brawl ... but it escalated VERY quickly -- with one very large man getting SMACKED over the head by a guy wielding a steel chair.
The guy who got hit didn't go down like they do in wrestling -- and fought back against the chair-wielder.
The Nashville Police Department tells us ... cops responded to a call about a "large fight" in the gym and quickly took control of the situation.
We're told no arrests were made -- but 2 people (a 46-year-old woman and a 37-year-old man) were treated at the scene for apparent minor injuries.
For the record, it doesn't appear Master P was involved in any of the fighting.
Still, Mick Foley would be proud ...