He is in allot of trouble. The distance between he and the guy standing up, the guy standing there was not approaching the fella on the ground.
Somebody goes to tuning on you, then after a couple of punches backs off...then you pop him, not good.
The attacker was still advancing until he saw the gun being drawn. If that guy hadn’t had the gun there is no doubt he would have gotten a kick to his head and likely could have been killed.