Charley Hull fired a 7-under-par 64 on Friday to take a two-stroke lead at The Ascendant LPGA in The Colony, Texas.
The Englishwoman rang up eight birdies and made just one bogey to post the low round of the day at Old American Golf Club. It brought her to 11-under 131, two ahead of Thailand's Atthaya Thitikul (67 on Friday) and China's Xiyu Lin (68).
Hull, 26, credited a hot putter, saying it had been the missing piece to her game.
"When I was home, I was working quite hard on my putting because I felt like that's the boringest part of the game to practice," Hull said. "I don't practice it as much as I should, so I've been doing like two hours each day and just trying to fix it."
Thitikul offset a double bogey at the par-4 ninth hole by eagling the par-5 17th. The 19-year-old won last week's Walmart NW Arkansas Championship and is in position to contend for her third victory of the season.
"Golf is challenging, because ... you change the course every week and then you have to adjust yourself to the course every week as well," Thitikul said. "Grass is different, green is different, wind, weather is different. So I think we get used to it, how to, you know, adjust to the course."
After leading the tournament by a shot after one round, Lin posted a steady round with four birdies and one bogey to stay in the hunt for her first LPGA win.
"I put in the practice and (I'm) telling myself ... what I have done and what I've been working on, and I'm willing to see the results," Lin said. "Obviously also trying to chase a win, so I think that just kind of keeps pushing me. Even (if) it's not a great day, I'm trying to do something."
Lindy Duncan posted a bogey-free 65 to move into fourth at 8 under. Jessica Korda (66), Denmark's Emily Kristine Pedersen (67) and Thailand's Moriya Jutanugarn (68) are tied for fifth at 7 under, and world No. 5 Lydia Ko of New Zealand (66) is in eighth at 6 under.
Notable players to miss the cut of 3 over par included South Korean major winner Sei Young Kim (4 over) and world No. 2 Nelly Korda (5 over).
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