Groves aims Twitter challenge at Nottingham's Froch

Boxer George Groves has posted an ultimatum on Twitter aimed at Carl Froch, saying the Nottingham fighter should either agree to a rematch or retire.

Froch stopped Groves during their super-middleweight bout in November, retaining his WBA and IBF titles.

Groves was however ahead on all three scorecards and looked the likelier winner, leading many to believe that the referee stepped in too soon.