John hadn't even heard Kyle's command. Like a wild animal fighting over territory or a mate he was locked in and oblivious of everything else. That was why the situation was so dangerous. It was likely that neither would stop till the other was dead or otherwise unable to continue. 

Just before Marcus made contact John thrust himself forward to counteract the hit. Between the anger and the head wound he was no longer thinking out his strikes. Blinded with rage he fought all out with Marcus. The two locked in a uncontrolled fit of punching, kicking, and any other means to bring their opponent down.