Yealimi Noh is looking to complete a spectacular LPGA debut as a professional.

It will be something special if the 17-year-old can win the Thornberry Creek Classic as a Monday qualifier.

Only two Monday qualifiers have ever won an LPGA event.

It’s beyond special if Noh wins beating the current Rolex world No. 1 and a pair of former No. 1s in a final-round showdown.

That’s the setup for Sunday’s finish at Thornberry Creek in Oneida, Wis.

“It feels really weird,” Noh said. “I wasn't expecting to be in this position. I'm really excited for tomorrow.”

Noh, who turned pro in January after a dynamic finish to her amateur career, will turn 18 in three weeks. She started Saturday one shot behind world No. 1 Sung Hyun Park. Noh didn’t look in awe at all playing alongside Park. She didn’t blink.

Instead, it was Park who looked ruffled late in the third round, opening the door to Noh and others with a double bogey and a bogey over the final four holes.

Noh was five shots back with four holes to play when Park stumbled.

"I was just like, 'Wow, she makes mistakes, too,'" Noh said. “Obviously, she's human, but it was surprising, because she was playing so well. To see that double I was like, 'Oh, even the No. 1 player does that.'"

At 20-under overall, Park left the course tied for the lead with former world No. 1s Ariya Jutanugarn (67) and Shanshan Feng (65) and with Tiffany Joh (66).

Noh (69) is one shot back.

“The third round wasn't my best, but I still am at the top of the leaderboard,” Park said. “There is still a chance for me to do well tomorrow.”

Noh, an American from Concord, Calif., won the U.S. Girls’ Junior, the Junior PGA Championship and Canadian Women’s Amateur in consecutive weeks last year. She has been playing mostly mini-tour events this year while trying to Monday qualify for LPGA and Symetra Tour events.

Brooke Henderson and Laurel Kean are the only players to win LPGA events as Monday qualifiers. Henderson won the 2015 Cambia Portland Classic and Laurel Kean the 2000 State Farm Classic.

Park appeared intent on following up her victory at the Walmart NW Arkansas Championship last week with a record-setting victory this week. With a hot start Saturday, Park was on pace to break the 72-hole LPGA scoring record set by Sei Young Kim at Thornberry Creek a year ago.

With seven birdies over the first 13 holes, Park built a three-shot lead, getting herself to 23 under.

But then Park knocked her second shot at the 15^th into the water. She followed that up three putting from 20 feet to make double bogey. An errant tee shot set up a bogey at the 16^th.

“I'm relieved that today was just the third round,” Park said. “I look forward to tomorrow's round.”

Ten players are within four shots of the lead on a course that yields birdies in bunches.

“It’s going to be a bit of a horse race tomorrow,” said Joh, 32, who is seeking her first LPGA title. “I'm just going to go out there and have a bunch of fun, and whatever happens, happens.”