GGG v Callum Smith, who wins?

Groves was at a disadvantage against the rangier Smith because he's a natural counter puncher who operates better off the back foot.
Smithy will have trouble with the forward pressure of Golovkin unless he can shut him out from the outside and I doubt he can do that. GGG will work his way inside behind the jab and lay some hard shots off Callums head.

 

What GGG looks like in his next fight is a guess, but moving up and fighting a competent fighter at 168 at his age is too much probably. Smith would probably be over 180 at fight time.