0-40.

He's not even in a winning position and he's got snatchy!!

Jeff Tarango
Former professional tennis player on BBC Radio 5 Live Sports Extra

I am totally freaked out by the no fans aspect. I don't like the fake noise they pipe in. I want to feel it like the players feel it. It's a really weird environment.

I appreciate the efforts to get this tournament off the ground but it's not the same without Nadal and Federer and the guys that test you in five sets in the early rounds.

Taken as Zverev digs a backhand out at the baseline but only lifts the ball about two inches.

Let's be blunt here, the fifth seed looks awful.

The Spaniard has a golden chance at the net to either lob or smack a forehand straight at Zverev to bring up break point again.

Instead the German wins the point.

Er...then Zverev double faults!

Two break points.

One break point.

Having said all that, how will PCB cope if he gets into a winning position.

We shall find out. He's heading to that point because he's 0-30.

Eek!!

The problem for Zverev is that he's expected to win this match - that pressure doesn't help a man who has yet to reach a Slam final.

Just saying.

A big serve out wide to the German's forehand side sees him cross the line.

The break advantage held.

Zverev looks tight. Very tight.

At 15-0 the German snatches at a forehand, looking for a quick winner down the line.

An ace brings up game point for PCB, but Zverev strikes back with a sumptuous angled shot which beats the sprint of his opponent.

Wait! Advantage Carreno Busta!

Taken as Zverev, with the entire court to hitm hooks wide - a good shot in cricket but not so much in tennis.

Leon Smith
GB Davis Cup captain on BBC Radio 5 Live Sports Extra

Pablo Carreno Busta is the old man of these semi-finals at the age of 29. It's usually the 30-something show but none of the familiar big names are here and we've got all these young new faces.

Another second serve, but PCB hits a weak double-handed backhand.

Deuce. That was a golden chance for the Spaniard.

The German once again goes long with a single-handed forehand from the baseline.

30s each.

Second serve coming up now... Zverev goes long again with a groundstroke.

Break point!

Zverev serves a second ace to get him out of a small pickle at 0-15 an then slams a forehand down at the toes of his opponent.

30-15.

David Law
BBC Radio 5 Live Sports Extra tennis commentator

It's such a surprise when you see how Zverev can serve. Hitting 140mph first serve seems like the easiest thing in the world when he's on song.

He brings the ball down from such a height he's almost unplayable, so I don't know what's happened.

Zverev goes wild with his forehand from the back - PCB survives a mini-scare.

We've already had 10 unforced errors from the pair in total. Neither have loosened up.

Russell Fuller
BBC tennis correspondent

Zverev's second serve is horrible to watch. It's really painful to see someone unable to serve, to have the yips like a golfer, you want to avert your eyes.

Break point for Zverev as PCB's two-handed backhand from the back fails to sail over the netting.

Saved by Zverev overstretching on his return.

The world number 27 tries the same trick again as Zverev comes in (a tactic no doubt) but this time fluffs his lines.

Deuce.

Zverev goes long before PCB passes him as the German approaches the net.

Game point.

A great rally at 0-15 should have finished 0-30 had Zverev done more with a volley at the net.

The next energy-sapping rally ends with the Spaniard finding the net.

15-30. Jitters PCB?