I felt that George did a way better job than Callum. Rebrasse is a solid gate keeper, but Callum is way to green for the likes against: Degale, Groves, Dirrell & so on.. He is not 1 fight away from a world title, Degale would school him and Groves might stop him.
DeGale is 4 years older than Smith with a longer career behind him. Groves is two years older, and Dirrell six years older. Regardless of which performance you rank the best (personally I thought Smith did very well vs Rebreasse), the kid is still years behind in the experience stakes - who knows where he'll be in five years time.
Did a great job against Rebrasse, because he was never in trouble I would rank it above Groves' win plus the fact that he actually hurt him too. Smith will beat them all soon, top quality talent however it is too soon for him yet.
he seems to have solid fundamentals, but as you guys mentioned, he's too green to be fighting guys like Groves or Jack give him Paul "The Wonderkid" Smith next, see how he does compared to Ward
