Urgh. That's horrid from Murray, a forehand drop shot that goes all sorts of wrong and ends up in the foot of the net.

He's not quite found his rhythm with his serve yet but an ace comes crashing down before he targets Del Potro's backhand. Deuce comes up as Murray overhits, but the Briton doesn't make the same mistake twice. He forces Del Potro to use that backhand, and the Argentine makes back-to-back errors. Murray will hold.

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Kyle Edmund's win percentage on his first serve was still a very impressive 88% in that second set. However, the problem was that he only landed 44% of his first serves.

Otherwise, the Briton did little wrong. If this was an arm wrestle then they'd be locked in the middle, with just a little movement to either side.

The tennis equivalent of an arm wrestle between The Rock and Jason Statham, if you like.

How will Murray respond?

A quick chunter to himself and he canters to 0-30, targeting Del Potro's backhand, before the Argentine thuds down two monstrous serve that send Murray sprawling. 30-30.

An ace down the T and another, cross court, to see out the game. That's a superb comeback from Del Potro, throwing all of that lanky body into the serve.

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Nice. Murray saves the first break point with an ace and then there's a superb rally, Murray up against it before he somehow, throwing his entire body to the right, manages to slap a winner to Del Potro's cracking forehand.

That's not what he was aiming for though, a loopy backhand, and Del Potro will take the first break.

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It's just dawned on me that I've never live-texted a Murray victory. So, er, sorry, Andy.

This is a touch messy from Murray, sending his forehand long, and he's not thrilled with his serve either. It's all a little floaty, a little out of rhythm, and Del Potro has cruised his way to three break points! Pressure on Murray...

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Kevin Anderson has lifted Kyle Edmund on to hook - and he isn't letting him climb off. Anderson's aggression in the tie-break pays dividends, a crackerjack of a forehand winner leaving Edmund wafting an thin Paris air.

The winner by the way will play Marin Cilic. The 2014 US Open champion has just cruised past Spain's Feliciano Lopez in straight sets.

What's Del Potro got? A stonking forehand, for starters, as the ball goes whizzing beyond Murray.

Murray's trying to take the pace off and the Argentine responds with a skip to the net and a tidy little drop shot. Even stevens, and the crowd respond with a polite round of applause.

* means next to serve

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Close. But not close enough. Anderson steps in, Edmund goes for the passing backhand, but it just misses the line.

Four set points for the South African soon become three. But he has two serves coming up...

...and that is exactly what the former world number 10 does. Now Edmund needs to reignite his service game, otherwise this set is going up in smoke.

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Advantage Anderson. Edmund slogs a forehand long, then responds with another brilliant double-handed backhand winner.

But the South African has a chance to open up a three-point lead on his serve...

On serve. Edmund loses the opening point, but hauls himself back into the breaker on Anderson's second service point with a deep forehand from the baseline which the South African can't control.

Ooft. Murray draws first blood with a backhand dink over the net, and Del Potro can't get near it.

Del Potro's beaten Murray once on clay, back in Madrid in 2009. The Briton claimed their other meeting on the red stuff in 2008, after Del Potro retired.

Another drop shot for Murray, and that's a simple hold first up.

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Now then. Edmund pegs Anderson back to 30-30 on the South African's serve as he aims to avoid the need for another breaker.

Unfortunately for the Brit, that is not possible, clipping the net and seeing the ball dribble into the tramlines as Anderson holds.

Deja vu. Tie-break time.

Right, here we go. Murray will serve first in front of a pretty empty crowd. World number one against world number 30.

It's been a mixed year for both these fellas, with Murray's season interrupted by injury and illness.

Del Potro hasn't had it easy either - he skipped the Australian Open as he fought his way back from a wrist injury.

The Argentine also struggled in the second round against Nicolas Almagro with a groin problem affecting his movement, but he said afterwards it was "not a source of concern".

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While we're on the subject of sports fashion, is tennis the worst-dressed sport out there? Or is it golf? Not sure.

Maybe Kevin Anderson is blinded by the glare from Kyle Edmund's luminous socks. Or maybe Edmund's service game is just too good. I'm going with the latter.

A hold to love. Beautiful.

The players are out over on Chatrier and having a hit. Del Potro's got a garish colour clash going on - purple kit, the same shorts as Kyle Edmund and bright yellow socks. I'm not having that. Murray's much more sedately dressed in white and navy.

Kyle Edmund goes 15-0 ahead when he pounces on a high bounce off the net with a forehand down the line...that is as good as it gets.

Anderson plugs in the power to go into turbo-charged mode, cracking a fiery forehand for 15-15 and then a pair of rockets for aces 10 and 11 of the match.

However, the month after Rio, it was Del Potro who prevailed in another lengthy epic.

Del Potro said at the time he was inspired by the loss at the Olympics as he came out on top after five hours and seven minutes.

It was, at the time, the longest match of either men's careers.

What we're saying is, don't expect this to be a quick match...

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Kyle Edmund's serve is looking untroubled at the moment. The British number two cruises into a 40-0 lead, although a double fault halts his progress a tad.

A long forehand gives Anderson hope, only for Edmund to pull another winner out of the top drawer to hold.

Now then, where's that pesky break?

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