Australia's Hannah Green made six consecutive birdies to close an 11-under-par 61 on Friday, and she holds the lead midway through the Ford Championship in Gilbert, Ariz.
The career-low round leaves Green at 14-under 130, one stroke ahead of Sarah Schmelzel and Taiwan's Peiyun Chien, who shot 63 and 65, respectively, at Seville Golf and Country Club.
South Korea's Hyo Joo Kim (67 on Friday) and Spain's Azahara Munoz (68) share fourth place at 12 under. First-round leader Pajaree Anannarukarn of Thailand (70), Japan's Yuka Saso (63), New Zealand's Lydia Ko (64) and Germany's Caroline Masson (65) are tied for sixth at 11 under.
World No. 1 Nelly Korda (68) is in a group of 12 players level at 10 under, tied for 10th place.
Green didn't wake up thinking she would produce the round of her life. She ended the bogey-free round with 11 birdies.
"I wasn't really feeling that great overnight," she said. "Kind of have a bit of a runny nose and sore throat, so wasn't expecting that much, which is maybe a good thing.
"I missed a short putt on the first (hole) and I was like, 'Oh, OK, that's fine.' I really took advantage of the shorter holes we had. I also holed a couple really long putts. Maybe even moved the hole. It was that firm. But just felt really good out there. Yeah, just had a really nice morning."
Green birdied five of the first 10 holes, then made back-to-back pars before her finishing charge.
"I did hole a couple short putts that I was able to hit close for birdie and a couple 10-footers," she said. "It's nice to see the ball go in and the reads that I had were correct.
"(Thursday) I actually didn't feel like I played that much different. I just read the greens a little better and hit putts that obviously went in."
Green is looking for her second victory of the month after she earned her fourth career LPGA title on March 3 at the HSBC Women's World Championship.
Schmelzel posted nine birdies and no bogeys in the second round. The 29-year-old Phoenix native is looking for her first LPGA win.
"I had quite a few family and friends out there today, so it was just awesome," she said. "One of my friends was fist-bumping me for every birdie, so we got pretty excited towards the back nine when we were tallying them up pretty good.
"But it just feels great to get some putts going in. It's always nice to see the momentum keep going, so just looking forward to (Saturday)."
Chien birdied four of her first six holes and also carded a bogey-free round.
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