When the fight starts remember that I'm on your side.
Tall ones are difficult to fight, especially if they have strong legs. Outrunning them for a distance, an average man is also disadvantaged.
But, with a broken pelvis, nobody can stand up, and it is not that terribly difficult to break. Men that are knowledgeable, quick, very short and well built also have an advantage.
One funny episode in my life was a very short friend of mine who was 5'2" and built like a D-cell battery. He took on this lean giant of a man built like a pro basketball player. Shorty ran him down like a bowling ball picking up a spare. It was a Kodak moment.