Jess Anderson
BBC Sport at Wimbledon

Barbora Krejcikova has left the court after that second set.

No doubt to have a word with herself. The defending champ has had a tough year since her victory here last year, struggling with a back injury which has seen her play just seven matches so far this year.

Can she get back on track?

Iga Swiatek turns away and shrugs her shoulders in the direction of her coach after sending long to trail 40-30.

Caty McNally goes on to get the hold.

Right then - almost time for the British number one...

Jack Draper made a comfortable passage through to round two - he was two sets to the good when opponent Sebastian Baez was forced to retire because of injury.

Marin Cilic is likely to provide a much sterner test today.

He may be 36 years of age now and down at 83 in the world rankings after an injury-hit spell, but the man from Croatia possesses a massive serve, is hugely comfortable on the grass and he has been all the way to the final at Wimbledon before, losing to Roger Federer in 2017.

Tracy Austin
Two-time Grand Slam champion on BBC TV

Caty McNally is doing a great job of disrupting the rhythm of Iga Swiatek, she's making it look so easy.

Swiatek is starting to feel rushed and she's not getting her first serves in.

McNally is starting to play better on Centre Court.

Caty McNally seems to lose focus in a rally and sends long.

Iga Swiatek isn't giving up the lead this time and the hold is sealed after saving three break points.

McNally will serve to stay in the set.

Iga Swiatek saves the second with a beautiful backhand.

And Swiatek kicks on further for deuce.

The eighth seed gets to advantage but gambles at the net but is beaten by a passing shot.

Krejcikova cannot get the break she needs and Carolina Dolehide has turned things around in this match.

We are back level in sets and the defending champion will need to lift her level again if she is to avoid relinquishing her Wimbledon title in the second round.

Where has this come from?

Caty McNally trailed 4-1 in this set but now has three break points and is on the verge of winning a fourth successive game to lead 5-4.

Caty McNally shows further resilience to come from 30-0 to get the hold.

Barbora Krejcikova is looking a little bit out of sorts.

The 17th seed is struggling with the ball toss on her serve and it is taking a few attempts before she is happy enough to hit it.

Carolina Dolehide, who is a break up again, pushes the defending champion to deuce but Krejcikova manages to squeak out of the game.

She will need to break if she is to stay in this second set.

Gary Rose
BBC Sport at Wimbledon

Image source, PA Media

A strong American presence in the crowd here on Centre Court and that break by Caty McNally prompted a big cheer.

She certainly had to work for it, as well as recover from the disappointment of seeing a shot by Iga Swiatek land in by millimetres at break point, but her battling display will give her encouragment after a tough start.

Image source, Getty Images

Caty McNally gets it on the fifth attempt!

A slow start to this match for the American but she is up and running now as we get back on serve.

Iga Swiatek saves again but she's only off the hook for a moment.

Caty McNally earns a fifth.

Iga Swiatek saves the first with a forehand winner and saves the second by mere millimetres.

Third time lucky? No. Swiatek gets to deuce.

But McNally with a drop gets another break point.

Tracy Austin
Two-time Grand Slam champion on BBC TV

Iga Swiatek has been impressive so far.

She hasn't been getting as many first serves in as she would want at 47%, but it doesn't matter because she is still winning her second serve points.

She is being ultra-aggressive yet consistent. She has really rushed Caty McNally, who is trying to target the Swiatek forehand.

What have we here?

Iga Swiatek goes big down the line and it's long.

Three break back points for Caty McNally.

It's a tough hold but it's a hold.

From 40-0 a lead to deuce - Caty McNally gets over the line.

Image source, Reuters

It wasn't going quite to plan for Barbora Krejcikova at the beginning of this second set.

The defending champion in the women's singles went an early break down to Carolina Dolehole.

However, like in the first set, Krejcikova has managed to get the break back and we are back on serve on court two.

Caty McNally is closing in on a hold to love until a double fault leaves the door slightly ajar for Iga Swiatek.

The eighth seed takes full advantage of that opening and fights back to deuce with a beautiful passing shot.