• American claims her 19th grand slam crown with 6-3, 7-6 triumph• Australian Open women’s singles final – as it happened in MelbourneSerena Williams shrugged off a coughing fit and a rain delay to win her 19th grand slam title in the Australian Open final on Saturday.Williams prevailed in the opening set against Maria Sharapova 6-3 on Rod Laver Arena before taking a second-set tie-break, extending her winning streak over the second seed to an incredible 16 matches.