Melbourne, Jan 19 : Jannik Sinner booked a ticket into the fourth round of the Australian Open with a 6-0, 6-1, 6-3 masterclass over 26th seed Sebastian Baez on Friday here at Margaret Court Arena. The fourth seed was in the driver's seat throughout, dropping just ten points on serve before wrapping up the win in 1 hour and 52 minutes. The Italian has reached the round of 16 in Melbourne for a third straight year and on Sunday, takes on 15th seed Karen Khachanov. By reaching a Grand Slam fourth round for the 11th time, Sinner broke a tie with Matteo Berrettini for second-most appearances by an Italian man at that stage of a major. His best major result was his Wimbledon semifinal showing last season. Earlier, Daniil Medvedev scripted an incredible story before everybody finally went to bed when he hit back from the brink to beat Finn Emil Ruusuvuori in a five-set thriller that finished in the early hours of Friday morning. Medvedev was outplayed by an inspired world No.53 during the opening two sets and was two points from defeat when he was serving at 4-5 in the fourth. The world No.3 used all his experience and resilience to turn the match around to somehow finish on top 3-6, 6-7(1-7), 6-4, 7-6(7-1) 6-0 in a contest lasting four hours and 23 minutes that finished at 3.39 am. It is the third time in Medvedev's career he has recovered from a two-set deficit at a major. He will play Canada's Felix Auger-Aliassime on Saturday for a place in the fourth round. /IANS