Carl Froch's coach from Birmingham, Rob McCracken, says they had worked on the knockout punch but also on left hook and body shots in the build-up to the fight.
Speaking after the biggest post-war fight in British boxing history, he also tipped Groves to bounce back:
"We practiced it a lot! We practised the left hook a lot and we practised his body shots too, which I think in fairness were a lot quicker that they were last time. He was pretty rapid when he got anywhere near George with the body punching and I think that slowed George down a little bit...
...But Carl Froch is a tremendous fighter, he's a prize fighter, he knows how to box, he knows how to fight and he knows how to win at the elite level and he's done that over the last six years consecutively and he went on to do that tonight...
...But, you know, Groves is a tremendous prospect and I'm sure he'll come again."
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ITV Central have launched a 60-second digital service for the General Election campaign. Here's the headlines for Wednesday 13th November.