Carl Froch settled his rivalry with George Groves in brutal fashion as he knocked his bitter enemy out cold with a crunching right hand in the eight round of their record-breaking Wembley Stadium rematch.

Groves blamed a moment of complacency on being caught by the knockout blow. "I felt I was ahead on the scorecards and I was in my groove, but I think complacency let me down," he said at the news conference.

"Carl Froch is a seasoned world champion and there's no quit in him. I was boxing very well but I let complacency creep in and that needs to be eliminated.

"I allowed Carl Froch into range and I paid the price for it. It was a split second that let me down. Until then I had been boxing very well. I felt I was winning comfortably. I was dominating him with the jab and he wasn't able to find his range.

"But I will come back stronger and I will be world champion," Groves said.