Roger Federer vs Kei Nishikori, Australian Open Day 7 Live Score Match Updates

But wait.. there was one match left to go - and it's been a massive upset! Angelique Kerber, who was defending her title in Australia, crashes out 2-6,3-6 to CoCo Vandeweghe of the USA.

Australian Open 2017: Roger Federer defeats Kei Nishikori in mammoth five-setter

Roger Federer beats Kei Nishikori 6-7(4), 6-4, 6-1, 4-6, 6-3, to reach his 13th Australian Open quarter-final in 14 years.

So, so so close - and after a challenge, it's in! Roger Federer, with an ace, WINS the match against Kei Nishikori!

Nishikori stays in it! Apart from one stray shot, he hasn't done too much wrong here. He's broken Federer's serve already and needs to break it here, trailing 3-5 in the final set.

Roger Federer to serve for the match.

Federer holds! He has 23 aces now - to Nishikori's 5, but the younger player is using Federer's forehand effectively against him.

Roger Federer leads 5-2 and Nishikori serves to stay in the match.

Nishikori survives! He's fighting and how. Guess it's not over till it's over, but Federer has pulled out some great points here. Nishikori's positivity is the most impressive here, and the Japanese ace has reached deep for some wonderful shots.

There's a great angled one-handed backhand from Nishikori to deny Federer a point, but the Swiss follows that up with an ace in his service game. And there's a quick forehand winner to finish as Federer leads 4-1 in the final set. Is this it for Nishikori?

Nishikori's depth is humongous, and he holds at a pressure time. He's managed now to hold that service game, a big one. He's finally opened his account in the final set to trail 1-3.

This might as well be match point for Federer. He's about to break Nishikori again, and there are some incredibly fast shots being played on court! Just as Federer looks set to break, Nishikori comes up with a great shot.

MTO for the same injury that affected him during the Brisbane final... pic.twitter.com/eScQrssj8L
— José Morgado (@josemorgado) January 22, 2017

It's not just Federer - it has seemed like all of the old guard have outlasted their younger counterparts and how! We saw that in the Rafael Nadal - Sascha Zverev match, we're seeing it now with Kei Nishikori, and we could well see it again.

Nishikori's struggling a bit with the pain here, and he's getting some physio on court now. The fifth seed is aching and in obvious discomfort.

And follows that up with his twenty-first ace of the match!

Go Federer! The Swiss gets the first break of serve in the final set and leads 2-0.

Federer races to a hold but Nishikori's fighting and how!

And there's a new level of tennis here from Kei Nishikori! He wins the fourth 6-4 and we'll see a fifth set here on Rod Laver Arena...

Nishikori looks motivated. After breaking - and being spurred on, he leads 5-3 in the fourth. And he's one break away from taking the match to a fifth set. Whaaat??

You got to be kidding me. pic.twitter.com/3FNlIj0kXp
— José Morgado (@josemorgado) January 22, 2017

Whew! That was a long, long service game! After 10 minutes and 7 seconds, Kei Nishikori pulls out all the stops to hold serve.

Scores at 2-2 in the fourth.

Service hold for Federer, but Nishikori has been impressive! He reaches the ball behind him, and another great running forehand goes to Federer.

Who returns it speedily.

Game Federer, leads 2-1 on serve.

Nishikori holds. Scores level at 1-1.

Top tennis from Nishikori! Having lost the last 5 games on a roll, he pulls back for some well-placed shots and out of nowhere, a service hold. He's pulling himself back together quickly.

There's a rare outburst from the usually calm Nishikori, who throws his racquet to the ground. Not nice. But he quickly pulls together and engages Federer in a powerful rally.

Game Federer 1-0 in the fourth. And how does he seal it? Two back-to-back aces.

Nishikori has only lost at a Slam three times after winning the first set. This one's going to at least four, though, and the sets are getting shorter.

Federer's winner to unforced error ratio quite strong at 8:7, Nishikori flagging a bit at 2:8.

26 minutes - that's how long it took for Roger Federer to seal the 3rd set, 6-1. Will the next set be the last one?

A ridiculously fast service hold from Federer - to love! Placement has been on point here, and the games are getting quicker and quicker. He leads 5-1 and Nishikori serves to stay in the third.

Federer leads 4-1 in this set now, with a couple of errors off Nishikori's racquet. It's falling apart a little bit for the 5th seed.

Some impressive shots from both players - that low volley by Federer, which was more than ably picked up by Nishikori - which Federer returned with a smash! Both the 5th seed and the 17th are in great form here, but at the moment it looks quite like Federer is dominating proceedings..

Federer builds on the break for a 3-1 lead!

Nishikori is very agile, though, and has sent Federer running quite a fair bit here.

And with yet another long, carefully constructed point, Federer takes the early break of serve in the third to lead 2-1.

Both players are properly stuck into the game now and on a rhythm. Nishikori's returning like a dream, but Federer sends an impressive volley to Nishikori with an almost flat racquet. Nobody would've got to that one!

1 set all, one game all for Roger Federer and Kei Nishikori...but not for long!

Lovely form from Nishikori going on here - and there's a stunning running forehand volley off the racquet of the Japanese ace. He seals out the game with a beautifully played point to hold. 1-0 to Nishikori in the third.

17 winners, 6 UE from Federer in that 2nd set. That's what it takes to win a set vs a good Nishikori.
— José Morgado (@josemorgado) January 22, 2017

Federer and Nadal dominating the Open... what year is this?

Roger on the run...#Federer evens the score v #Nishikori, taking the 2nd set 6-4. #AusOpen pic.twitter.com/FiA3e5NpN0
— #AusOpen (@AustralianOpen) January 22, 2017

Breaking - is Federer, and so is Nishikori's serve! Right now, the Swiss comes thundering back into this match with a 6-4 second set win. This will have been essential for him both mentally and physically to stay in this match, although he's been one of the most successful players coming from two sets down.

Federer's up a break in the second set now, leading Nishikori 4-3!

That was one of the longest games so far! Some well-constructed points from Federer, but Nishikori's more than held his own here. The 5th seed is sending some lightning fast forehand winners into the tramlines into areas they won't really be retrieved. Great stuff from both players here.

Scores are at 3-3 as Nishikori misses out on a slice there. He's defending extremely well, though - and awaits Mischa Zverev in the next round if he wins.

Interesting fact - @rogerfederer's first ever Slam win was at 2000 #AusOpen - vs a certain Michael Chang, who now coaches Kei Nishikori.
— Anuradha Santhanam (@anumccartney) January 22, 2017

Jumping backhand smash, as you do, Roger Federer.

It's all going smoothly for both players in this set, but not ideally for either.

An ace from Federer! But Nishikori battles back to win the first set on a tiebreak.

Nishikori's up a mini-break at the first change of ends and he's playing some great defensive tennis - but Federer grabs the mini break back! Nishikori leads 5-3.

Nishikori leads 3-1 in the tiebreak!