Roger Federer has won his way through to an Australian Open quarterfinal for the 13th time, the 17-time Grand Slam champion seeing off Kei Nishikori 6-7(4) 6-4 6-1 4-6 6-3 at Rod Laver Arena on Sunday night.
Nishikori led 5-1 in the first set before Federer recovered to send it to a tiebreak, and despite losing that set, the Swiss roared through the next two to be within touching distance of the last eight.
The Japanese rallied to force the match into a decider, but had treatment on what appeared to be a lower back injury at the beginning of the final set, and again after Federer took a 3-0 lead.
Federer was untroubled from there as he defeated the Japanese for a fourth consecutive time.
Seeded 17th on his comeback to Grand Slam play, Federer will play world No.50 Mischa Zverev in the final eight, after the German stunned world No.1 and top seed Andy Murray in four sets earlier on Sunday.