Federer ousts Nishikori in classic five-setter

Roger Federer has sent a massive statement to his remaining Australian Open rivals, knocking out fifth seed Kei Nishikori in the fourth round.

The world No.17 warmed into the contest and overcame the hard-running Japanese with a 6-7 (4-7) 6-4 6-1 4-6 6-3 win on Sunday night in three hours and 24 minutes.

Nishikori made all the running early and took a commanding 5-1 lead in the first set, and only escaped with the lead in a tense tiebreaker.

The Fed is back! Image: Getty

From there Federer went about staging a brilliant fightback, taking the next two sets before a momentary hiccup in the fourth.

Nishikori's body began to break down in the fifth, requiring treatment on his hip, and Federer took full toll, setting up a quarter final clash with Andy Murray's conquerer Mischa Zverev.

"He's got a great five-set record, he's a tough customer so this is a huge win for me in my career," Federer said after the match.

Against Tom Berdych in the third round Federer was irrepressible from the get-go, but on Sunday night he took a little longer to hit full stride.

Federer didn't face a break point all night against the Czech world No.10 but on Sunday he gave away eight in his opening two service games, falling 4-0 behind.

But Federer finished over the top of Nishikori, perhaps due to his troubled hip, and never looked like losing the fifth set.

The win was Federer's 200th against top-10 opposition, a record.

It also ended a four-year drought in five-set matches against a top 10 opponent.

Federer has an incredible chance to claim his 18th grand slam and fifth Australian Open after the early exit of top two seeds Murray and Novak Djokovic.

It is the first time since 2004 that the top two men's seeds have failed to reach the quarter-finals of a grand slam.

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