It all went down Saturday afternoon at the Nike 3ON3 tournament at L.A. Live ... where Horry's son was playing. Witnesses tell us a man affiliated with the opposing team was heckling Horry throughout the game when he approached R.H. and pushed him. Horry responded with his fists ... throwing several punches at the man. It's unclear if any of the punches landed. We spoke to Horry who insists he was simply defending himself. "The guy was trash talking the whole game. He shoved me. Where I'm from, you protect yourself."