Pretty much what MFKS said, but he also left out the incident where Brockie or Smith (I think it was Brockie) kicked at Birighitti when he collected the ball, and Mitchell got involved straight away with some shoving.
The actually tackle that sparked the brawl wasn't that bad imo, Wellington bloke got underneath Tiago, Tiago's momentum carried him over the top of the other du, it was kind of 50-50. Other du blows it and hits Tiago while he's getting up, mass brawl ensues
Oh yeah and you might be right about your boy Mitchell, not sure how good he is defensively but at least in terms of communication and experience he's a real leader from the back. More importantly though he seems to have adopted Dutchy's gameplan perfectly.