20-yr-old Tsitsipas knocks defending champ Federer out of Aus Open
Greece's 20-year-old Stefanos Tsitsipas knocked two-time defending champion Roger Federer out of Australian Open in the fourth round on Sunday. Tsitsipas defeated the 37-year-old with the scoreline of 6-7(11-13), 7-6(7-3), 7-5, 7-6(7-5) in 3 hours and 45 minutes. This is only the sixth time in last 20 Australian Open editions that six-time champion Federer has failed to reach the quarter-finals.