Serena Williams is not prepared to put a number on the haul of majors she might end up winning after claiming her 23rd title with her Australian Open triumph. Serena, who won her first major at the US Open in 1999, drew level with Graf’s tally of 22 at Wimbledon last year and edged ahead of the German with her 6-4, 6-4 victory over her sister Venus on Rod Laver Arena on Saturday.