CALLUM SMITH is in a curious position. Out in Nuremberg, preparing to box Nieky Holzken, a kickboxer adapting to boxing, in a fight he surely will win, a fight he must win. It’s the World Boxing Super Series semi-final. Victory will guarantee Smith a shot at WBA super-middleweight world champion George Groves. “It’s a huge fight for me,” Smith said of Groves. “There’s a lot at stake.”If he doesn’t beat Holzken “the big fight’s gone”. He continued, “It’s not just this fight, it’s what comes after it.