Image source, afp

And this is why Novak Djokovic is rapidly becoming one of the greats. The 10-time Grand Slam winner puts himself in pole position to make that 11, wearing Murray down in deuce at the pivotal time.

Murray thinks he has coasted to a simple hold-to-love service game, finishing off Novak with a cross-court forehand into the corner.

But it appears not. the chair umpire calls it out, Murray challenges, and the official is proved spot on.

Djokovic takes heart from that let-off, stepping forward to crack a forehand winner for 40-30.

The pair go toe-to-toe at the baseline again...a marathon 36-shot rally ending when Murray goes fractionally wide. Deuce...

Pat Cash
Former Wimbledon champion on BBC Radio 5 live

"He's overall become a tougher player. His volleys and serve have come on a bit. He's almost a 1% man. He keeps adding a little bit onto great performances."

Image source, AFP

Of course breaking the Djokovic serve is easier said than done. And so it proves for Andy Murray.

Another massive Murray backhand leaves Djokovic wafting at thin air....15-30. 

But Murray, two points from the set now, lets Djokovic back in when he doesn't give a forehand enough beef. 

The Briton's trusty weapon - that backhand - lets him down at 30-30 and another poor execution of that shot leaves Djokovic celebrating the hold.

Even his coach Boris Becker lets off a huge sigh of relief.

Pat Cash
Former Wimbledon champion on BBC Radio 5 live

"That's a massive hold. In the last few games he has pumped up the power. He's taken his spinach and found Popeye power.

"By and large, Murray's winning the long rallies."

Brian Smallwood: Watching Murray is like betting on Grand National. Painful to watch & likely to lose but hoping horse makes a decent attempt!

Sam Cornwell: Djokovic is the Ivan Drago of tennis. "I must break you".

Nice Rocky reference, Sam. Maybe we should start belting out Eye of the Tiger?

Image source, AFP

This is the game that neither man can win. It is all on the Briton's racquet - each point won by a Murray winner or lost by a Murray error. 

A thumping cross-court backhand cannot be diverted back over the net by Djokovic at deuce number four and Murray does eventually get over the line when the Serb clatters a backhand into the tape.

Now the Briton just needs another break of serve to win the second set...

Image source, AFP

But back comes Murray! Another superb second serve arcs away from a floundering Djokovic to save that break point and force deuce. Murray can't convert at the first attempt but another ace - his 10th of the match - tees up another chance to wrap this game up...

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Boom! Murray wallops down a thunderous ace to start his service game. Crash! He batters down another for 30-0. The Briton is revitalised!

Wait...a sloppy forehand reduces the gap to 30-15, prompting Murray to moan about the flashbulb lights going off in the crowd.

A sliced backhand from Murray doesn't hit the spot...30-30...then he can't dig out a forehand return when Djokovic goes deep.

Break point to Djokovic...

Pat Cash
Former Wimbledon champion on BBC Radio 5 live

Image source, AFP

"Murray's almost at a stage where he's got nothing to lose. He's throwing the kitchen sink at Djokovic."

Carolyn McTaggart: Yes Andy! Let's go Andy let's go.

James Diamond: Superb show of mental strength from Murray to break back. Momentum is slowly shifting his way.

Jeffery Samuel: GAME ON!!!!

Image source, AFP

First break point for Murray since the opening game of the match - and he takes it. Or has he?! Murray thinks so, Djoko doesn't. The Serb challenges Carlos Ramos's call - and he's wrong.

Murray's cross-court backhand is inch perfect, clipping the very outside of the tramline, inches from the baseline.

The Melbourne crowd whoop and holler...they're not keen on being shortchanged by a three-set final...

If you needed any indication of how frustrated Murray is then we've just seen it. The Briton uses some, ahem, choice language as he fidgets on his chair at the changeover. Perhaps he should be wearing that 'warning: explicit language' slogan that his missus had on her jumper last year...

Jamie Leadbetter: Why is it so infuriating watching Andy Murray? Because you know he's good enough, he just makes too many unforced errors.

Tim Bell: Murray's got his body in the oven now, but needs his head in the fridge for those finesse moments.

Roy: Murray getting a game out of Djokovic today is as hard as breaking into a safe by scratching at it furiously with fingernails. 

Image source, AFP

What Murray needs is a comfortable service game - and then heap the pressure on the Djokovic serve. Ah...

An opening double fault sets the tone for Murray, who shouts and screams at his box, before allowing Djokovic to muscle his way into a 40-30 lead - and a break point.

Djokovic sniffs blood, pushing and pulling Murray all over the baseline. Murray keeps responding until finally buckling with a long forehand.

Murray got himself back into the rally then crumbled quicker than an overcooked apple pie.

Image source, AFP

Close but not close enough for Murray. Groans from the Rod Laver Arena as the second seed drills into the tape from close range to hand advantage to Djokovic. They're backing the Briton.

He briefly offers them - himself - hope as Djokovic's stray backhand means the game goes back to deuce. But Djokovic puts his foot down as he batters the Murray backhand into submission.

David Law
Radio 5 live sports extra commentator

"If it's an arm wrestle, Andy Murray would win. 

"Murray is like Popeye. Djokovic is like a greyhound."

You can listen to David alongside former Wimbledon champion Pat Cash on BBC Radio 5 live by clicking on the live tab at the top of this page. 

Image source, AFP

Djokovic slaps a backhand into the net for 15-30, bringing a rare show of negative emotion from the usually-serene Serb. He angrily slaps a ball into the blue acrylic but responds with a serve that Murray can't keep in play.

30-30...another long rally, Djoko probing both the Murray forehand and backhand. Murray blinks first, mis-hitting an ordinary forehand into the tape for 40-30.

But Murray grows into another rally, stepping in with some crunching forehands, and a scrabbling Djokovic crumbles with a return into the net. Deuce...

Pamela Dobbie: Come on Andy...more like this please ...cracking point!

Dennis Ethan: Andy Murray's passing shots are the best.

John O: Second set is now looking more competitive. Murray is now back in it.

Pat Cash
Former Wimbledon champion on BBC Radio 5 live

"What really would have driven Andy nuts is if he'd missed that shot after that set up.

"He's back in this one now."