Dom Inglot
Former British tennis player on BBC TV

I think Tiafoe is able to build some momentum here. Choinski tried to steady the ship but Tiafoe, it's almost like a fire was lit under him after losing the first set. He realised 'I need to go in to a new gear because I've got a very formidable opponent who is not going to give me everything easy'.

Not for the first time, Caty McNally double-faults on break point.

This time it's a loose forehand from Caty McNally. Third time lucky for Elena Rybakina?

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Caty McNally saves another break point, this time with a T serve that a scrambling Elena Rybakina puts into the net.

The problem for Caty McNally is that when Elena Rybakina connects with one of her serves, it comes back with interest.

Saved with a quick serve into Elena Rybakina's body.

Frances Tiafoe is in full flow now.

A huge serve wraps up the second set. Momentum is firmly on the side of the American now.

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Dear, oh dear.

Caty McNally is up 30-0 but concedes three quick points to find herself facing another break point. She hasn't held serve since her opening service game.

Frances Tiafoe takes complete control.

The American will serve for the set.

Well, that was a bit of a procession. Elena Rybakina has places to be, people to see, and has raced through the first set with two breaks of serve - 6-1.

She had a huge drop off against Lois Boisson, dropping the second set 6-1, so she'll be hoping to avoid that and get the job done in a brisk two today.

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Jan Choinski falls 30-0 behind but turns up the aggression and gets the reward with a volley winner at the net.

Choinski recovers for 30-30 but fires wide with a backhand to hand over break point.

Elena Rybakina crushes a volley for 40-15. Two set points for the second seed.

Dom Inglot
Former British tennis player on BBC TV

I think Choinski will be delighted with the way it's gone. I think it was a really hard fought first set. Even though he had a lot of opportunities you have to give credit to Tiafoe; he stepped up when he had break points, coming up with big serves.

Tiafoe took it out of the hands of Choinski but he stayed resolute in his determination to get that break and he ended up doing it on the 11th attempt.

No panic from Frances Tiafoe as he gets the hold.

Both players end up stood at the net, looking at the ball at McNally's feet.

Elena Rybakina has the double-break. She's cruising.

Mark Woodforde
17-time Grand Slam doubles champion on BBC Radio 5 Live

I don't want to say that alarm bells should be ringing for Frances Tiafoe right now. He has that comfort break of serve, but I just feel like he should be trying to play a bit more proactively.

Up the other end, Jan Choinski just has to remember he has a set on his side. If he ultimately loses this set, the match will still be balanced.

Image source, PA Media

Frances Tiafoe looks a lot more composed than he did in the first set. The 17th seed guides a passing shot into the corner and then follows with his third ace of the match for 40-30.

But an awkward bounce off the baseline scrapes off Tiafoe's racquet and wide to offer Jan Choinski hope.

Elena Rybakina is looking quite unstoppable when she gets on top of the baseline. Caty McNally keeps trying to neutralise her, taking pace off the ball, but Rybakina manipulates her position until the avenue opens up for a down-the-line forehand. 30-all.

After hunting down a drop shot on her forehand, she races across the net for a backhand volley winner. Uh oh.

Jeff Tarango
Former American tennis player on BBC Radio 5 Live

One thing we have to remember is Jakub Mensik won his first-round match in the super tie-breaker, the match was four and a half hours long, so Grigor Dimitrov has that in his favour.

There is a chance the Czech might get tired, although he is 20 years old and one of the fittest players I've seen. It might be the case that he is a quarter of a step slower, though.

Nine break points and counting now for Jakub Mensik, who just can't get over the line in a Grigor Dimitrov service game.

Dimitrov is finding a way when it really matters.