Leona Maguire insists she must remain disciplined and patient if she’s to become the first Irish woman to win a Major after finishing a birdie to take a one-shot lead into the final round of the KPMPG Women's PGA at Baltusrol.

The world number 12 carded a two-under 69 to lead on seven-under-par from South Korea's Jenny Shin and by two shots from her friend and former Irish teammate Stephanie Meadow, who putted brilliantly and carded a four-under 67 to sit alone on in third on five-under in New Jersey.

Riding the momentum of her second LPGA win last Sunday, Maguire (28) admitted she lost her discipline at times but planned to try and treat Sunday like any other round, even if it promises to be the biggest of her career.

"It was a little bit more of a mixed bag, but I felt like I hung in really well," Maguire said after her eighth consecutive round in the sixties. "I had a few key up and downs out of bunkers to keep me going and it's always nice to finish with a birdie.

"Any time you break 70 in a major championship golf course, you are pretty happy; so nice to have done it for the third day in a row."

One clear of 2021 Solheim Cup partner Mel Reid (67), Norwegian rookie Celine Borge (69) and China's Xiyu Lin (71) on five-under-par overnight, Maguire birdied the first and seventh to extend her lead to three shots through the turn.

But she had to dig deep in between to build that lead, making a 10-footer at the third to avoid a three-putt and a six-footer for par at the fourth for par.

While she missed a good birdie chance from eight feet at the fifth, she got up and down from sand for birdie at the seventh, making a 10-footer there before getting up and down again from sand for par at the ninth.

She lipped out for birdie from around nine feet at the 10th, then three putted the 11th from around 45 feet, lipping out from four feet to find herself tied with Shin, who shot a bogey-free 66 to equal the low round of the week.

The Ballyconnell battler would regain the lead with a birdie from around 15 feet at the 15th, but the finish stretch was a challenge.

She dropped a shot at the par-five 17th, where she was bunkered in three after being forced to lay up 225 yards from the green after a rare drive into heavy rough.

But she two-putted the last from 33 feet for a stress-free closing birdie and a one-shot lead over one-time LPGA Tour winner Shin, who is also seeking her first Major.

“It’s the first time I'd ever been in that position feel like I handled it pretty well,” Maguire said of her first Major lead. “Try not to treat it any differently than any other round. Just like last week.  

“So I think the same mindset tomorrow, just me and (my caddie) Dermot will enjoy one more walk around this really nice golf course tomorrow.

“I wasn't quite as disciplined today maybe as I should have been. We picked really good targets. I kind of just got off on them a little bit on the back nine. But yeah, for the most part, executing really well, and just need to do that again tomorrow.”

She’s certainly not planning her celebration party just yet though she knows what an Irish win would mean back home.

“I think there's there's a lot of business to take care of between now and then,” she joked when asked if she would celebrate in Shane Lowry mode. “So we’re not getting too far ahead of ourselves. I think Dermot said Seamus Power is actually here today, which was just cool to see.  

“I mean, it's never been done before and obviously, there's a lot on the line tomorrow, but I’m trying to treat it no different than any other day.

“I have massive support back home. Always do. Irish fans are the best fans in the world there. They're rooting me on. I think there were quite a few out there today as well.  

“I haven't been paying too much attention to social media this week and won't tonight again. I’ll just keep on doing what I've been doing and keep my head down for one more day.”

In a fairytale scenario for Irish women’s golf, she will have one of her oldest friends and rivals breathing down her neck.

Meadow played superbly, dropping her only shot of the day at the 10th as she birdied the first, seventh, 11th, 14th and 15 for her 67.

"You know, putter got hot a little bit, which is always nice, but I hit a lot of really good shots as well," said Meadow, who leads the field on the greens despite missing an excellent birdie chance at the 18th.  

"I gave myself a lot of opportunities and just didn't put myself in any terrible spots, which is also a big key out here."

The Antrim star (31) is trying to stay on an even keel by insisting golf doesn't define her and that she's lucky to do what she does.

But she knows Sunday could be a huge day for Irish women's golf with her friend of 18 years also seeking her first Major win.

"'I'll put it this way, I knew her when she was reading Harry Potter books, so that was a long time ago," she joked of her long relationship with the Cavan star.

She added: "I can't think of anything much better for Irish women's golf, which is incredible.  

"We have been close. I mean, we've known each other since -- I mean, she was probably 10, and I was 13 or something like that. So it's been quite the journey together for both of us to make it.

"Obviously, I was there last week when she won. It was great to kind of share that moment with her. I know how hard she works. I know how hard everybody works out here.

“Yeah, we're great friends, and we stay on the road together sometimes. So it's just great for Irish golf."

The Jordanstown star is seeking her first win in the US after a career marked by injury and the tragic death of her father and greatest supporter, Robert, from cancer in 2015 after he had moved the family to the US when she was 14 to help her chase her dream.

"Obviously, we all think about (winning)," she said. “That's our dream. I think it would be silly to say that I don't think about it.

"But I think about it, but I know what I have to do to get the job done. So I'll just stay in the process and get a good night's rest if I can and come out and give it my all tomorrow.”

Maguire’s caddie Dermot Byrne has been her secret weapon and she admitted he’s been a massive help since he started on her bag in 2021.

“I think that the biggest thing is he's given me the confidence,” she said. “I think he's believed in me in times where I haven't believed in myself, and he's just a really steady presence out there.  

“I think he doesn't get too excited when things are going well. He doesn't get too down when things aren't. And I think we're quite similar in that regard.  

“We’ll just enjoy one last walk together this week, and then he's been here before. I think the experience he has, having been here for a men's major, he knew how the golf course was going to change how things might be set up. So I think that was a nice sort of added bonus to have this week.”

As for her long relationship with Meadow, she said: “I've probably known Stephanie. since 10 or 11 years old. We would have played on Ulster teams together; we would have played on Irish teams together. We played Curtis Cup together. We played foursomes together; we roomed together.  

“Yeah, I've known Steph a long time. We've been good friends a long time. And we've done battle many times before and it's great to see her playing so well.”

Maguire’s twin sister Lisa arrived in New Jersey on Saturday and she could be a calming influence as she faces the biggest day of her career on Sunday.

“I think just staying patient,” Leona said of the key to Sunday. “One more day of patience. I know it's a cliche, but I think this golf course really demands it. And just one more day of being super patient and really disciplined out there.”

It's far more than a three-horse race, however, with China’s Ruoning Yin (69), South Africa’s Lee-Anne Pace (70), American Lauren Coughlin (68) and world number one Jin Young Ko (69)  tied for fourth just four shots behind on three-under.