Wow. Some of the "defence"/mitigation on here for the altercation is quite amusing.
Hohaia must have said something - you can see him looking at Flower for a few secs before turning and running to chase ball.
As he does, Flower comes in with a swinging arm that makes contact with the head. Hohaia clearly takes offence to this and runs back and shoves him across the top of the chest/side of his cheek with forearm. Wasn't an elbow, nor was it particularly "aggressive" with intent to cause injury - more a bit of handbags.
Flower punches him square in the face back, knocking him out. Then punches him from what I can see on the eye socket. Flower falls on him and is looking at him. There's enough time to pull out and/or realise the man is unconscious.
Should be banned for 8+ in sporting terms.