Postpublished at 13:47 BST 5 June 2018
*Zverev 3-5 Thiem
Zinger. That's hot off the strings of Alexander Zverev. He needs to punch in a few more points like that.
But Dominic Thiem is proving a proper nuisance to the German at the moment.
30-15.
Novak Djokovic loses to unseeded Italian Marco Cecchinato
World number 72 wins 6-3 7-6 (7-4) 1-6 7-6 (13-11) to reach semi-finals
Djokovic struggled with shoulder/neck problem early on
Austrian seventh seed Dominic Thiem beats Alexander Zverev 6-4 6-2 6-1
German second seed Zverev had hamstring problem
Madison Keys beats Yulia Putintseva 7-6 6-4 in women's quarter-finals
Sloane Stephens beats Daria Kasatkina 6-3 6-1
Michael Emons and Alex Bysouth
*Zverev 3-5 Thiem
Zinger. That's hot off the strings of Alexander Zverev. He needs to punch in a few more points like that.
But Dominic Thiem is proving a proper nuisance to the German at the moment.
30-15.
Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra
Dominic Thiem is holding serve so quickly. He's only dropped five points so far.
He's hit eight winners and only six unforced errors.
Jonathan Jurejko
BBC Sport at Roland Garros
My German isn't too hot, but I do know a swear word when I hear one. And there are few curses being uttered by the German contingent in the press box.
That tells you what they think about their man Zverev's performance so far.
*Zverev 3-5 Thiem
Ace. Thiem holds. Zverev now has to serve to stay in the first set.
Zverev 3-4 Thiem*
Thiem on the defensive, Zverev giving him the runaround and dictating the point.
But somehow it's the seventh seed who comes up trumps. And a furious Zverev then goes wide.
40-15.
Zverev 3-4 Thiem*
Can Dominic Thiem consolidate that break?
Alexander Zverev pops a forehand long, but follows up with a snapping winner that kisses the line and flicks away from the Austrian.
15-15.
Jonathan Jurejko
BBC Sport at Roland Garros
No proper whiff of a break for either player until that game - although the signs were already there that Thiem was going to earn a chance sooner or later.
The Austrian has won 10 of the 24 points on Zverev's serve (42%), compared to just four earned so far by the German (25%).
Yulia Putintseva 5-5 Madison Keys*
Yulia Putintseva was serving for the first set, but she can't take the opportunity as American Madison Keys breaks back thanks to two great returns, a drop shot and then a powerful forehand after a long rally and we are back on serve. 5-5 in the opener.
Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra
Zverev has been a little bit sluggish and Thiem slightly the better player.
Zverev has hit 10 unforced errors and only five winners.
Zverev 3-4 Thiem*
Magnificent crosscourt winner from Dominic Thiem! Some serious whip in that backhand.
The Austrian breaks.
*Zverev 3-3 Thiem
Big, wide serve from Zverev to force Thiem towards the advertising hoardings, before hammering a forehand winner into the space left behind.
But he cracks the tape with a deep forehand and as the ball loops wide it hands Thiem two break points.
*Zverev 3-3 Thiem
Well, Zverev isn't impressed a at towering forehand being called long. He strolls over, but that point is heading in Thiem's direction.
The German smashes another beyond the baseline.
0-30.
Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra
Maybe Zverev was a bit stiff at the start and they were both a little bit tense but the quality has stepped up now.
*Zverev 3-3 Thiem
Zverev looks to have soaked up an extended round of thumping Thiem groundstrokes, returning them with interest, only to then slice a forehand narrowly long.
Thiem holds, it stays on serve.
Zverev 3-2 Thiem*
Lashings of forehand followed by a side of sliced backhand before Zverev drifts in and fails to convert.
He gets Thiem on the run on the next point, closes the angle and this time the Austrian shoots wide with a flat forehand.
15-15.
*Yulia Putintseva 4-3 Madison Keys
An early advantage for Yulia Putintseva over in the opening women's quarter-final.
We were on serve, but the world number 98 has just gained a break, successfully taking her first break point.
Madison Keys will be keen to stamp out the unforced errors. Seven mistakes from her compared to only three from Putintseva.
Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra
It's great to hear that Andy Murray is making progress because we've really missed him. He's such a great player and a great role model for the sport and I can't wait to see him back on the court again.
Click here for the latest report on Andy Murray's fitness.
Zverev 3-2 Thiem*
Thiem's not quite firing in this game, another backhand drifts off target and he shrugs his shoulders in disbelief.
But the seventh seed shows extreme speed to scuttle across the clay and reach a sliding Zverev drop shot before coaxing it back beyond the giant German.
Zverev then serves out.
*Zverev 2-2 Thiem
Fantastic pick up from Thiem at mid-court, but he drives his next forehand long.
The Austrian takes on a Zverev serve from way behind the baseline and loops it into the tramlines.
30-0.
Leon Smith
GB Davis Cup captain on BBC Radio 5 live sports extra
The court is playing a lot heavier than usual because of the moisture but it looks like Zverev is slightly slower than we've seen him, which is understandable given the court time he has spent to get this far.