Lydia Ko competing in the women's individual golf tournament at the Paris Olympics. Photo: Inpho / www.photosport.nz

New Zealand golfer Lydia Ko says she's got nothing to lose as she chases a third straight Olympic medal tonight.

Ko took the joint lead after the fourth round, catching pacesetter Morgane Metraux of Switzerland to set up a tense final round at Le Golf National south of Paris. American Rose Zhang and Japan's Miyu Yamashita are tied in third at seven under par.

Ko, for whom gold in Paris would complete her Olympic set, maintained her consistency to reach nine under par at the end of the penultimate round.

Ko won silver in Rio in 2016 and bronze in Tokyo three years ago. A few years ago the 27-year old had the Olympic rings tattooed on her right bicep to mark her achievement at the 2016 Rio Olympics.

A gold medal in Paris would mean she would become just the sixth New Zealander to have won a medal of every colour at a summer Olympics.

"Yes it would be the Cinderella story if I win gold here," Ko told RNZ a few days ago.

Metraux is an Olympic debutant after choosing not to go to Tokyo while chasing a spot on the prestigious LPGA tour, which opened the way for her sister Kim to represent Switzerland three years ago.

In contrast, Ko has been in the mix at each Olympic golf competition since the sport returned to the Games in Rio.

Does Ko think her previous Olympic experience will be a factor during the final round?

"All aside, it's pretty cool that all three of the Olympics that I played in, I'm in the final group for all three of them. I actually didn't think of that until a couple of days ago. It's kind of like a bucket list that has been checked.

"Because I have two medals under my belt, I kind of feel like I've got nothing to lose. I know that I'm going to give it my all, and I'm going to try my 100 percent. If it's meant to happen, it's going to happen," Ko said.

Ko knows she's in a unique position heading into the final round.

"The Olympics doesn't come around every single day, and definitely not even every single year. So to be in this kind of position is awesome, and I'm excited to just kind of embrace all of this.

"I know that feeling, standing on the podium, is definitely a once-in-a-lifetime kind of emotion that you feel. I would love to feel that again tomorrow, but there's still 18 very difficult holes in front of me, so I'm just going to focus on that and see where that puts me."

Ko said she didn't normally keep a close watch on the leaderboard but it was hard to avoid.

"Everywhere I turn there's a leaderboard. So, it's really hard to not look when there's names there. At times, I think it is important because you need to know where you are, what you need to do. And I think these final few holes can create a lot of drama ...a lot can change, so in ways it's good to look, but I've been doing really well just focusing on me and sticking to my strategy."

Ko revealed she had taken inspiration from US gymnastics star Simone Biles after watching a Netflix documentary a couple of days ago, which chronicles Biles struggles.

"I just had it downloaded and I'm actually off social [media]. I deleted my Instagram app just for the week because I didn't want other things to distract me. Obviously, it shows how much time I'm on my Instagram that I was like, 'Oh, what do I do?' So I watched her documentary called Rising. It was so inspirational.

"As an outsider, we never know what the person is going through. For her to have been so vulnerable, it inspires a lot of people. And it inspired me. I loved a few of the quotes that she had said, so I wrote them on my yardage book."

Ko said a certain quote stood out for her.

"One of the things she said was, 'I get to write my own ending'. Sometimes we get carried on about things that we can't control. And if I can do a good job of the things I can control, the rest is out of my hands.

"I always say, 'I want to be the one that's determining my fate and my ending and how I end my career, my round'. That (quote) just sunk in with me a lot."

Biles of course left Paris a few days ago with three golds and a silver, to hands down become the greatest gymnast of her generation.

"If tomorrow all goes the way I would imagine it or dream of it to be, that would also be the perfect quote to kind of say that. But with this golf course, it doesn't matter if you're four, five or six shots behind, you could potentially be really in it," Ko said.

The final round tees off at 7pm on Saturday.