This is the biggest pot of bullshit I've ever read.
First off the police aren't "regular" citizens and they've received training in unarmed combat. One of the first things most cops are told is that they are not out there to "fight fair". They should not be confronting "dangerous" individuals alone and should always request backup.
Cops are out there to protect and serve. They aren't there as a proving grounds for their martial prowess. And they will be in situations with people at the worst possible point in life. It behooves them to respect that, respect all life, remember they are there to keep the peace and order.
Hate to tell you this but shit happens.
He was calling for backup when Gentle Mr Michael Brown sucker-punched him.
I suppose while the kid was trying to grab his gun and murder him to escape apprehension for a strong-arm robbery minutes prior to the attack, he should have just said that's okay, we don't want to disturb the peace and tranquility of the neighborhood. Meanwhile the officer was fighting for his life.
That kid was dangerous and letting him go was not an option.