It turns out that Guillermo Rigondeaux’s left hand is not broken. Complaining of pain on the top of his left hand, Rigondeaux, a southpaw, simply quit after the sixth round of what had been an utterly one-sided domination by the brilliant junior lightweight world champion Vasiliy Lomachenko on Saturday night in their heavily hyped fight at the Theater at Madison Square Garden in New York. It was the only time that two-time Olympic gold medalists had ever met in a professional boxing ring and Rigondeaux (17-1, 11 KOs) shocked many by getting outclassed and quitting. Now it looks even worse for him since the hand is not broken and he had no major injury. “No break, but severe contusion on left hand,” Dino Duva, Rigondeaux’s promoter from Roc Nation Sports, told ESPN via text message on Tuesday. Rigondeaux, a reigning junior featherweight world titleholder, moved up two weight classes for the bout and, because he lost, he is due to be stripped of the belt as part of the WBA’s pre-fight ruling.