Swiss stuns fifth seed to reach 49th career quarter-final
jamuna news desk: This was only Federer's fourth official match since returning from six months out with injury but the Swiss stayed tough on Rod Laver Arena to win 6-7 (4/7), 6-4, 6-1, 4-6, 6-3 in three hours and 24 minutes
Roger Federer cast off doubts about his fitness by winning a five-set thriller with Kei Nishikori to reach the Australian Open quarter-finals.
He will now continue his pursuit of an 18th grand slam title against Mischa Zverev, the world No 50 who had earlier pulled off a shock win over top seed Andy Murray.
Federer's previous five-set match came at Wimbledon last year when he was beaten by Canada's Milos Raonic in the semi-finals, two days after winning a decider against Marin Cilic.
The Swiss will be hoping to avoid a similar hangover this time around, particularly given the draw has opened up for him following Murray's surprise early exit.