GGG is a lot better than Kov in terms of skill and technique, may be a bit stronger too at his weight. Kov may hit a little harder and a little quicker on the draw, but GGG is better technically- punch combinations, counter-punching and foot movement. Particularly GGG's uncanny knack to "switch" power/lead feet- some call it "shifting" or "switching".
With GGG, you are just never sure where the power shot will land from if you are watching his chest or keeping pace with his feet. More than just him giving you awkward angles, but when he advances you are just not sure where you may be hit from HARD.
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