Nishikori is still struggling to get his forehand returns the right side of the baseline, but finally one comes off and it earns him break point at 40-30.

Djokovic brings it straight back to deuce, but hits long himself and it's advantage Nishikori.

Now there's a bit of deuce-advantage-deuce action again. 

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Nishikori matches Djokovic with his fifth ace of the game to lead 30-15.

The pair get going in a nice little rally and Djokovic is screeching left-to-right across court, returning like a boss, but eventually he can't race back in time to meet Nishikori's gentle return. 

The Japanese takes the game, much to his relief. 

Djokovic takes a 30-0 lead and makes it 40-0 with his fifth ace of the match. Easy does it.

A love game ensues. Nishikori needs to wake up a bit. 

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At times, Nishikori can hit some glorious shots. At other times, he hits some complete duffers.

He tries to jump and execute a big lob and it goes way out. And I mean way out.

Nishikori switches off again and Djokovic comes racing into the net and earns two break points with a sensational back-hand.

And he takes the game to go 4-1 up. 

A waaaaaaahey from the crowd and a rather sunburnt spectator has caught the ball. Who doesn't love that?

Djokovic goes 40-30 up and wins the game on his second serve, as Nishikori can only skew his return horribly wide.

Nishikori has racked up 23 unforced errors, and his forehand is not looking too pretty.

He's 0-40 down - three break points for Djokovic. 

An almighty ace from Nishikori and a duff overhead return from Djokovic and we're at deuce. 

Advantage Nishikori with another ace and eventually he holds his serve. Big sigh of relief from the large Japanese fanbase in the crowd

Image source, AP

Nishikori has got a little bit of spark about him now and it's annoying Djokovic, you can tell.

The Japanese seventh seed flings himself across court and the score is back to deuce. 

Advantage Nishikori...but Djokovic brings out a huge ace..so we're back to deuce again. 

Finally Djokovic takes the game.  

Hmmm...a double fault by Djokovic and it's 15-15, but luckily for the Serb his opponent's forehand is still all over the shop and he hits long over the baseline.

Djokovic slams a low forehand into the net and we're level again. 

But what a return from Nishikori! The Japanese flies through the air and scoops a backhand across court, and he earns his first break point. 

Djokovic brings it back to deuce, and then gets an advantage, but Nishikori draws the top seed into the net and it's deuce again. 

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Nishikori is looking nervous. He doesn't have the big serve to match his opponent and his returns are going wide or in the net.

Djokovic has two break points. And the collapse continues as Nishikori slices wide again. 

Game Djokovic, and it's his chance to serve.

Ooooh, a double fault from Djokovic. That's one each now in the first set.

And a poor, poor backhand from the Serb hits the net. It's 0-30. 

The world number one composes himself and, with his third ace, makes it 30-30.

A wonderful rally ensues and Nishikori hits long. It's set point.

Another review for Nishikori on the baseline. Djokovic is already walking off, he's certain it's long...and it is. Djokovic takes it.

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Nishikori is serving to stay in the first set. His first serve hits the net. Oops.

But he gets his second in and finishes the point with a lovely, gentle back-hand cross-court.

The seventh seed does serve it out and takes a love game. That's the way to do it.

Nishikori is still shaking his head after that last game, and Djokovic is powering on. 

The world number one comes into the net and Nishikori slams his return wide to make it 30-0. 

An ace from Djokovic bring him to eight straight points. Oh, actually, make that nine. 

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A great drive volley from Nishikori makes it 15-0. 

It looks like it's going to a third love game...but wait...Nishikori sees two returns go into the net and it's 40-30.

And now he hits long and it's deuce. Djokovic plays a brilliant forehand which hits the line and it's the Serb's advantage. 

Double fault Nishikori. He's choked. Djokovic breaks.  

These two don't like coming anywhere near the net. They're like crabs skulking sideways across the baseline. 

Djokovic's serve is on point, and he takes a 40-15 lead before finally coming into the net and swiping cross-court to finish the game off.

That's five games in 15 minutes. Speed demons, these two.

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One helluva ace from Nishikori to open the third game. 

But the Japanese loses his first point on serve as Djokovic's forehand tricks him out wide. 30-15.

Nishikori challenges a call on his backhand return but it is judged to be out....just.

Has it rattled the seventh seed? Djokovic takes it to deuce, but the Serb hits a weak return into the net and and then, after slipping and sliding across court, sees his forehand go long and Nishikori takes the game.

Back on Djokovic's serve and it's another love game. The second in a row. 

Two quick games for two quick baseline players. 

Slow down lads, I can't keep up over here.  

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Nishikori is a big fan of the back-hand winner. The Japanese slams it down court for 15-0 and Djokovic has no chance of a return.

And as quick as you like, Nishikori takes the game to love. 

The crowd cheer as the players come on court and boom! An opening ace from Djokovic. What a way to start.

Nishikori levels with a lovely backhand straight down the flank and it's 15-30 as Djokovic drags his return wide.

A deep breath from the Serb and he wins his service game with Nishikori putting his final shot way beyond the baseline. 

Britain's Jamie Murray and his new doubles partner Bruno Soares of Brazil have made it through to the semi-finals with a win over South Africa's Raven Klaasen and Rajeev Ram of the USA in three sets. 

Djokovic and Nishikori are out on court having a bit of a warm-up. 

Seems to be plenty of support for the Japanese man in the crowd. Face paints, flags and everything.