Thiem lashes down an ace for 30-0 - only his second of the evening - and backs that up with another crushing forehand to move within one of the hold.

That is clinched and another tie-break will decide this set, possibly the match...

Right then, Thiem's time to hold serve. If he doesn't we're going to a fourth.

Neat and very tidy. Medvedev holds to love after landing some hefty first serves.

Momentum back to Thiem then. Will it stay with him or swing back to Medvedev? I've no idea and I'm not making a bold prediction.

Three on the bounce for the Austrian second seed as he gets over the line from 40-30.

WOW!! What. A. Point.

I didn't think this rally would ever end, both players raining blows on the other.

A 38-shot duel (THIRTY-EIGHT) ends when Thiem soups up with a big backhand and follows it up with the put-away.

Medvedev fails to serve out for the second set running...

Oh! Medvedev spoons one on set point. Lifeline for Thiem.

Medvedev challenges the next point, wrongly, losing his final lifeline.

Break point Thiem...

Thiem, sensing danger, springs into life. He ups the ante to move 30-15 ahead, only for Medvedev to reassert control with a forehand winner and a serve/volley.

Set point...

If Medvedev is going to claw a set back, he's gonna have to do it on his own serve.

Thiem quickly races 40-0 ahead, then after a slight blip, whacks down a 135mph service winner.

He ain't going to do that this time. Solid hold to love from the Russian third seed, who forces Thiem into errors on both wings.

Big hold. But will it be enough? We will know more after this next game. Medvedev squandered a 4-2 lead in the second set...

Saved! A ripper of a backhand down the line just when Thiem needs it. The second seed sees off the break point.

If you're just joining us (?!) Thiem has been unable to convert two break points - one in the first game and one then in the fifth.

Now it is Medvedev's turn to have another good look at his opponent's serve. The Russian dumps a backhand from deep in the court into the net.

Obviously, he was unhappy at slipping... but not sure if he's blaming sweat on the baseline or his shoes. Maybe both. Nicht gut!

Medvedev can't get over the line there, but he does two points later. That comes moments after Thiem slips on the baseline, leading to some uncharacteristic and prolonged shouting from the Austrian.

My long-forgotten GCSE German can't decipher what he's angry at.

Thiem tries to spread himself at the net like Peter Schmeichel, but doesn't quite have the wingspan.

Back to deuce. Then it is A-40 Medvedev after a 118 ace out wide.

Medvedev continues to come forward at opportune times, doing it again twice to lead 40-15.

Not a straightforward hold though as he allows Thiem to battle back... deuce.

Then an lengthy rally ends when Medvedev slices a backhand long. Break point Thiem...

I've had my fair share of sporting injuries but never done my Achilles. Painful, right?

Thiem is definitely dragging that leg around at the end of a game. During it though, it doesn't bother him too adversely. A hold to love.

Rapid hold to love from the Russian. Halfway to the set... fire up the kettle.

Some Hendrix keeps everyone rocking and rolling at the changeover.

He's got it! Medvedev is scampering along the baseline, sending everything back to Thiem. The Austrian loses patience and a wild backhand goes well wide.

Like in the second set, Medvedev breaks early and leads...

Medvedev moves forward to the net, Thiem tries to pass him... a tad long. Break point for the Russian...