Feng Shanshan is going to have the president of the United States looking over her shoulder in the final round of the US Women's Open, and probably a lot of South Korean fans, too.

The 27-year-old from China rolled in a short birdie putt on the final hole on Saturday to take a one-shot lead after three rounds of the biggest tournament in women's golf.

Teenager Choi Hye-jin Choi and perennial Open bridesmaid Amy Yang were tied for second in an event where the South Koreans have dominated.

The top six players chasing Feng are all from South Korea, and you have to go all the way to eighth place to find a US player. That's Cristie Kerr, who was five shots off the lead.

It should make for an interesting final day in a tournament that had an even bigger stage with Trump in attendance. He's the first sitting president to attend a US Women's Open.

Feng shot a 1-under 71 to reach 9-under 207 at the president's Trump National Golf Club in Bedminster, New Jersey.

"Coming to this week, I didn't have any expectation at all," said Feng, who has led from the start after shooting a 66 in her quest for a second major. "I just wanted to bring out my ‘A' game. And then I think I did really well for the first three days, and then I'm going to stick to my game plan. I just focus on my own game and let's see what happens."

Choi and Yang each shot 70.

Park Sung-hyun, the top rookie on the LPGA Tour, was 6 under after a 67. Top-ranked Ryu So-yeon (71), , the only two-time winner this year on the LPGA Tour, Lee Mi-rim (67) and Lee Jeong-eun (73) were 5 under.

Kerr, a former Open winner and a member at this course, was tied at 4 under with Spain's Carlota Ciganda (72).

Feng had a one-shot lead after the first round and a two-shot margin at the halfway point, but she just could not hit it close in the third round. She had a couple of 10- to 15-footers for birdie on the back nine that never threatened the hole and she did not convert until hitting her third on the par-5 18th to about 5 feet.

Feng's only major victory came at the 2012 LPGA Championship, her first US triumph. She has followed with six more US LPGA titles, most recently winning in May at Ann Arbor, Michigan.

Choi, 17, who is the world's No. 2 ranked amateur, might have been the most consistent player after bogeying her first hole. She birdied Nos. 8, 11 and 16 and just missed another on the final hole.

Yang, who has four top-five finishes in the last five years, including seconds in 2012 and ‘15, had a roller-coaster round. She had five 5s, a bogey and a double bogey, which came on No. 3 after a bad shot out of a bunker.

With the arrival of the president on Friday afternoon, security was stepped up on Saturday. Dogs sniffed cars driven by players entering the course and fans and media had to walk through airport-type security checkpoints.

Trump spent the night in his house on the course and took the short drive from his residence to his box overlooking the 15th green, arriving around 2:35pm. Walking up the stairs, he yelled to the crowd asking them about the players' scores.

Stacy Lewis, a former No. 1 who has not won since 2014, played her first 10 holes in 5 under and moved within a shot of the lead heading to No. 11. However, she flubbed a couple of chips near the green and took a triple bogey. Her day ended miserable with a 10 on 18, leaving her at 2 over.

Defending champion Brittany Lang saw any chance of repeating end with an 8-over 80.