Britain's Georgia Hall birdied two of the last three holes to seize a two-stroke lead over Australia's Minjee Lee after Saturday's third round of the LPGA Portland Classic.
The 22-year-old from England, who won her first major title at last month's Women's British Open, recovered from an opening bogey to fire a three-under par 69 at Columbia Edgewater Country Club.
That put LPGA rookie Hall on 18-under 198 after 54 holes with Lee, who stumbled with a bogey at the par-4 17th, on 200 and American Marina Alex a distant third on 204.
No other rival was within eight shots of Hall, who began the day with a three-stroke lead and played a stalwart round as rivals faded.
"I didn't start amazing, but the pin positions were probably the toughest the week so far, and the wind got up a bit, so yeah, I'm happy," Hall said. "I've got a two-shot lead. There's still a lot of golf to play, but looking forward to tomorrow."
Hall had back-to-back birdies at the par-5 fifth and par-4 sixth and again at the par-3 16th and 17, then sank a testy four-footer for par at 18 after a lip-out for birdie.
"You know, 16 and 17 are tough holes, especially with both pin positions, so I was very happy to hole some putts that I didn't really hole much," Hall said.
Lee sandwiched two birdies around a bogey in the first three holes, then torched three par-5 holes -- the fifth, seventh and 10th -- for birdies and added another at 11 before falling two off the pace with her late stumble.
After a poor drive left her behind a tree root at 19, Lee admitted share was scared she would hit the root on her second shot. She pitched out and saved a bogey.
Lee hopes for a fast start Sunday in what could become a one-on-one duel for the title in the final pairing.
"There are a lot of opportunities out here, so whenever I get a chance, I'll try and take advantage," Lee said.
"I don't know where the pin placements are going to be, and if they're tucked they're really hard to get to, especially if you're not in the fairway. Then you really have to take your medicine and just play to the middle of the green."
Canada's Brooke Henderson, coming off a Canadian Open title, fired a 74 after three bogeys in a row from the 14th to 16th holes, falling 11 shots behind Hall.