Ireland's Leona Maguire and American Jennifer Kupcho combined to fire a 10-under par 60 in best-ball to grab the lead after Friday's second round of the LPGA Dow Championship pairs event.
The back-nine starters united for eight birdies and an eagle to shoot the low round of the day at Midland Golf Club in Michigan and stand on 13-under 127 after 36 holes.
"We ham and egged it really well," Kupcho said. "She made a lot of really good putts today and yesterday also. We'll just keep it going."
Scotland's Gemma Dryburgh and Australian rookie Cassie Porter, the 18-hole leaders, combined for a 62 to stand second, one shot back on 128.
"We complement each other really well. We have different strengths and kind of play to those," Dryburgh said. "We got going on the front. We had a lot of good putts."
Maguire birdied three of the last six holes, closing the round with six straight one-putt greens, and credited her partner with setting her up for a solid putting effort.
"Her length off the tee has been an advantage this week," Maguire said. "I think we're real fierce competitors and you see that in the Solheim Cup and week to week so I guess we're putting down our swords this week and coming together. Has been fun so far."
An alternate-shot (foursomes) format will be used on Saturday with best ball again for Sunday's last round.
"Just continue to hit fairways and greens and give each other putts," Kupcho said of their plans. "Just put ourselves in the best position and see what we can do."
It was a big day for Porter, who made five birdies in a row from the par-five third through the par-three seventh. After she and Dryburgh both had bogeys at the eighth, Porter birdied the next four holes to reach 12-under before they closed with six pars.
"We both made plenty of putts," said Porter. "You can go pretty low if you've both got the putter hot. We just made putts at the right time and helped each other out."