Top seed Sania Mirza quelled a late challenge from American wildcard Laura Granville to enter the quarter-finals of the US $75,000 ITF Vancuover Open on Thursday.
Croatia's Mirjana Lucic-Baroni, who made the third round of the 1997 US Open also at 15, was the previous youngest player to advance to that stage of a grand slam.
Images from the Australian Open matches played at Melbourne Park on Wednesday.