Lydia Ko remains one off the lead after a regulation par on the long fifth. Most of the players seem to be struggling to reach this back pin with their second shots, given it's 85 yards onto the green.

I wonder if she'd take 13 more pars from here? Given the tricky wind conditions five under may be enough to pick up the trophy.

What do you think? Hit the thumbs... thumbs up if six under or better wins, thumbs down if it's five under or worse.

Mao Saigo is the latest to join the growing group gathering at three under par. The Japanese rolls in from 15 feet for birdie on the short eighth - her third in four holes.

The back nine is playing ridiculously tough though, with only three under par rounds on the closing stretch, so this is going to be a battle of who can hang on best.

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Jenny Shin pulls her tee shot on the fifth. Out of nowhere, a double and now in potential trouble.

Just like that, she has plenty of work to do after starting in contention.

Jeeno Thitikul is back to where she started the day after a birdie on the long fifth.

The 21-year-old from Thailand, who has had a spell as world number one in her short career, opened with successive bogeys today but a birdie on the third and this latest one means she's just three back.

"A typical Scottish day" is the weather update on comms. Take from that what you will. Wet and windy!

Jiyai Shin hammers her long putt up to six foot and smiles. You have to love her personality, smiling with every shot. No stress, just loving every minute.

After dropping a shot, that was needed big time, and she makes no mistake this time with her par putt.

Lilia Vu pulls her birdie putt and taps it in for par as well.

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I love Lottie Woad's approach to putting. Every single one so far today has been hit with purpose. The latest is a 25-footer for birdie on the sixth, and while it doesn't drop, she gives it every chance and leaves herself a foot or so back for par.

It's increasingly looking like she might end the day as the highest placed finisher from these shores, which I'm sure she'd have taken at the start of the week.

Another shot goes for Charley Hull and that may well be race run for the Englishwoman who is now six off the lead.

Hull led after shooting a five-under 67 in round one and followed that with a 72 on Friday as the players battled winds gusting to 40mph.

A three-over 75 on Saturday saw her fall five off the pace and she just hasn't been able to get on a birdie-run on what is, arguably, the easier of the nine holes on the Old Course.

Make that four! Four holes and four birdie chances for Nelly Korda.

This one was tougher for Korda, who knocks her 15-footer up to gimme range, she is playing some tidy golf and just needs to sink a few of them ones.

Jenny Shin makes double bogey after a horrid time.

Lottie Woad reaches the par-five fifth green in two but she's about 200 feet from the pin. I kid you not!

For those of you unfamiliar with the Old Course at St Andrews, the fifth green is about 100 yards deep. That's about the length of a football pitch.

Woad's ball got on to the front of the green. The hole has been cut 85 yards on. 85 yards! That's a good wedge for most of us.

She's out with the putter though and that is an incredible effort, thwacking the ball a couple of yards long and maybe 15 feet wide. The birdie putt doesn't drop and that goes down on the card, perhaps cruelly, as a three-putt par.

Lilia Vu and Jiyai Shin both hit two safe shots into the centre of the green. They both knock it up to the hole, with Vu tapping it in easily.

However, Shin puts a little bit too much on her putt, she then misses a nervy six-footer for par.

Vu now goes into the co-lead with Shin, who walks away smiling. If only I could stay that calm...

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While the leaders are leaving birdie putts on the green, Lydia Ko shows them how to get it done with her first of this final round on the fourth.

It's a snaking left-to-righter from 20 feet that tracks beautifully all the way.

Here is Charley Hull, down the right of the sixth hole and she's been in a bit of bother in the gorse by the looks of things and has taken a penalty drop from an unplayable lie.

Her third is a sparkling effort though, grazing the flagstick as it bounds 20 feet past the hole. Big par saver coming up though...

... she gives it a rattle up the slope but the ball doesn't want to come back in from the right and ends up six inches beyond the hole. Bogey.

Three birdie putts, three pars. Nelly Korda's approach play has been bang on, but that one from around 12 foot is pulled slightly.

Jenny Shin from even closer then does the same.

Whoever gets the putter hot will win this one!

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We're not seeing much of Charley Hull which can only mean one thing, she's not yet started charging up the leaderboard.

A fifth successive par for the Englishwoman who remains five adrift of the lead.

Lilia Vu is next to come so close to nailing a mega-putt. I reckon that was well over 30 foot. It looked to be curling into the hole, but it just fades away. A tap in par is not bad from that far away.

Jiyai Shin has a 12-footer for birdie and that one comes up just short.

Again, both will be happy with pars.

Another par ticked off for Lydia Ko who judges a monster birdie putt across the third green to almost perfection.

It's got to be a 50-footer, climbing up and over a mound, than flattening out towards the flag, where her ball comes to rest about six inches from the hole.

Nelly Korda has a 15-footer for birdie, which comes up agonisingly short - if you blow on the ball it might go in!

The world number one's approach play has been spot on so far.

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After being in a spot of bother, Lilia Vu produces a lovely soft chip from off the back of the first green before sinking a 12-footer for par.

Before that, Jiyai Shin flicks her putter up in the air as her 20-foot birdie putt just comes up short. She taps it in for par and both are off to solid starts.