Ivo Karlovic comes out of the longest game of the match so far, clinging onto his serve.

It is still intact in the third set - but it looks as safe as a Ming vase at a coconut shy with Murray still deep in the groove.

Just when you think you have seen this film before, Andy Murray provides a plot twist.

Down 40-0, the Briton cuts Karlovic down to size with a fizzing return at his kneecaps and then sends a cascading lob over the top to take himself into deuce.

Break point Murray...and a lob chance...

Nope, Murray fails to connect cleanly and Karlovic slaps away the smash to save break point.

The Croat is not out of the woods yet though...

Image source, Getty Images

Andy Murray knocks off his own service game to love.

Fifteen minutes gone in this third set and four games nailed to the board. The stroke count per rally is looking skinny.

Ivo Karlovic's serve machine spits out two aces on its way to a hold to love.

The Croat is accelerating away from Murray in the ace count now, leading 10-6.

Image source, AP

If it was the start of a comeback, it was snuffed out sharpish by Andy Murray.

The Scot dumps down a bucketload of ace to extinguish the embers.

Is this the start of a resurgence for Ivo Karlovic?

A swiped return winner and a wrong-footing forehand takes the Croat to deuce for only the second time in the match.

James Taylor: Much more impressive from Murray. Seems he's shaken off whatever was on his mind the other day. More hopeful now about tournament.

Ivo Karlovic's usual deft hands at the net desert him as he cuffs over baseline from what should have been a routine bounce.

That gives him 30-30 and Murray is circling, sensing service blood.

Karlovic cranks down a serve so wide, so full of kick that most other players would need a stepladder to recreate it.

The Croat is through unscathed, but it is a struggle every time.

Alix Ramsay
Journalist, The Scotsman, on BBC Radio 5 live sports extra

"Andy Murray has now spent 63 minutes on court today and won two sets. He'll be very pleased with that. He's rattling through and doing everything he wants to do. He needs to work on the drop shots but everything is going well."

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Clinical.

Andy Murray ratchets up the service speed and is 40-0 and shooting at three set points.

Riding that sort of cushion, the Scot can go for broke. A forehand drilled down the line is a fraction long.

In the end Karlovic does the job himself, drifting long and surrendering meekly.

Just an hour on the clock.

Andy Murray teases a looping lob over the top of Ivo Karlovic, but cannot land the ball in play.

He will have to close out this second set on his own serve. Ivo Karlovic is yet to force a single break point and has made deuce just the once.

Alix Ramsay
Journalist, The Scotsman, on BBC Radio 5 live sports extra

"He's not the most natural mover in the world, Ivo Karlovic. It takes a little while to get those long legs moving across the court in the same direction at speed."

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Andy Murray's drop-shot. When it is good, it is gorgeous. When it is bad, it is hair-tuggingly infuriating.

The Briton dollies one into mid-court for Ivo Karlovic to bash away and set himself up with 0-30 and a chance to force break point.

Murray goes back to the tried and tested playbook for taking on Karlovic, shifting the big man side to side and working his way back to 30-30.

A cute poke down the line, a serve into the body and Murray makes good his getaway.

But that was a note to the Scot's self - keep it simple.

Alix Ramsay
Journalist, The Scotsman, on BBC Radio 5 live sports extra

"Andy Murray has now worked on his second serve a lot. He can go for broke on the first serve, knowing that his second serve is also a valuable weapon."

Image source, Getty Images

Ivo Karlovic strides though the game like the BFG doing his nightly dream rounds. A hold to love.

Andy Murray's physio is called Mark Bender in a case of nominative determinism that has passed me by until now.

Andy Murray knuckles down from 15-15, drawing an error from Karlovic at the baseline, before plucking an ace from the quiver and then finding another big serve in his locker.

Four aces each so far.

Andy Murray with some show-stopping line-finders during that game, but he plants another ambitious punt just wide to allow Ivo Karlovic to scurry to safety.

It is some big game the Scot is hunting out there, but he already has had the Karlovic serve stuffed and mounted several times in this match.

Andy Murray with a lovely angled backhand brings up two break points.

He cradled that one cross-court as gently as if his racquet handle was a baby bird.

Ivo Karlovic marches him down though, banging down serves and chasing in to take the game to deuce. 

Image source, AP

Alix Ramsay
Journalist, The Scotsman, on BBC Radio 5 live sports extra

"He'll be able to get this match done and bath his daughter Sophia at this rate. The family are here in Paris, but I imagine Kim has her hands full at the moment."