The Abrams Tank is reputed to be the world's premier tank, but it isn't without its vulnerabilities; its turret sides and rear, as well as the engine compartment/engine air intake at the back, are prone to damage, and its top is also quite fragile.
The armed insurgents in Mosul have obviously studied the weaknesses of this American tank, targeting its critical areas.
Moreover, this particular Abrams Tank had its depleted armor removed, making it absolutely inferior to the fully equipped version used by the US Army.
Even before the rocket had hit the tank, the heavy machine gunner in the Humvee behind it had already swiveled his gun around, ready to sweep the rooftop insurgent with fire and send him to his maker.
Unexpectedly, just as the gun was turned and before he could fire, the hidden sniper took another shot.
A 7.62 caliber sniper bullet passed through the gap in the machine gun's shield and struck the machine gunner right in the throat.