Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

Safe to say from this juncture, it is the mental side of how Jakub Mensik approaches it. Does he believe he has three sets in him? He has got to outplay Alexander Zverev. It is going to be a task ahead.

Jakub Mensik holds to 15 but it's far from clean. Four second serves and a poorly executed drop shot which Alexander Zverev punishes.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

In this first service game, Jakub Mensik needs to try to play his cleanest game possible.

Image source, Getty Images

Naomi Broady
Former British player on BBC Radio 5 Sports Extra 2

Alexander Zverev said if he played his best tennis to date it would be 90% on his racquet and I agree with him. If he is playing his best tennis, then there is a reason he is ranked where he is.

Alexander Zverev seals the second set at the first attempt, overpowering Jakub Mensik with a forehand.

That set flew by. Two breaks of serve for Zverev and only three points given away on his own serve.

In the blink of an eye, Alexander Zverev has three set points.

Muted applause around Court Philippe-Chatrier. Perhaps they sense this could be over quite quickly.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

You can't have a 100% record when you try to explore going forward. It is a pathway to winning, but you have to accept that you are going to lose points as well.

Deary me, another one of those pesky double faults. Jakub Mensik had saved one break point but only has himself to blame on the second.

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Jakub Mensik pulls out an ace at 0-30 down but finds himself facing a couple of break points after failing to react to a fizzing cross-court backhand while stood up at the net. Not quite sure what happened there. He didn't even stick out his racquet.

Image source, Getty Images

An equally rapid hold to love for Alexander Zverev. Quick points, forcing errors with his serve.

The camera picks out a woman in the crowd - possibly mother Zverev? - who offers up a fist pump with gusto.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

Only the second time Jakub Mensik has held serve to love. An indicator that he still has not felt his stride in this match.

Jakub Mensik races through a hold to love. He looks pretty emotionless throughout.

Image source, Getty Images

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

Watching Jakub Mensik as the point went against him, and his body language is not glowing like it was in the first set.

That was key for Alexander Zverev as it maintains that buffer. The scoreboard pressure is right there for Mensik.

Naomi Broady
Former British player on BBC Radio 5 Sports Extra 2

It felt like an important few minutes that. Alexander Zverev needed to step on it here...

Alexander Zverev responds to the double fault in style, pinging down a wide serve which is returned into the net and following it with an ace out wide.

Jakub Mensik looks crestfallen.

Image source, Getty Images

Alexander Zverev toys with the Czech. A backhand drop shot is chased down by Jakub Mensik, who plays his forehand cross-court, but as he tries to cover the down-the-line winner, Zverev plays the ball right back to where he was. 30-0.

But from 40-0, he's pegged back to 40-30 and then double faults for deuce.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

These are indicators. Alexander Zverev is on the front front from the previous game. It seems like he is growing in confidence with winning the first set.

Image source, EPA

Once again, Jakub Mensik turns to the drop shot. Alexander Zverev is wise to it and pings a forehand tight across the net at a hideous angle and although Mensik scrambles to recover it, the German is in place to bury a backhand winner.

Momentum has well and truly swung in the German's favour.

Oh, Alexander Zverev's forehand is starting to purr.

Jakub Mensik comes on quite a tentative approach at 15-30 and Zverev whips a cross-court forehand winner around him. Two break points.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Sports Extra 2 and BBC Sounds

Alexander Zverev is sometimes so adamant from the other end of the court that he has clipped the line. It is so excessive, and he starts the conversation, then there is a battle within.