Florentyna Parker fired a three-under 69 to join Carly Booth and Stacy Lee Bregman in a three-way tie at the top of the Ladies Scottish Open leaderboard.
France's Anne-Lise Caudal had enjoyed a two-shot lead from Sarah Kemp overnight, but both went round in a disappointing 76 on Friday to fall away.
Having made the turn at one-under, Caudal suffered four straight bogeys and then a fifth on the 17th hole to drop away.
"It's too cold; it wasn't easy out there," said Caudal on the Ladies European Tour website. "I didn't putt very well today and I had a bad shot on 17."
Kemp was undone by a double bogey on the 16th.
That opened the door for a new set of leaders to emerge, and Parker propelled herself to the top with a best of the day round of 69.
An eagle on the par-five sixth had her fiiring, and although she bogeyed two holes on the back nine, three birdies had her heading in the right direction.
Scotland's Booth birdied the 18th to ensure herself a share of the lead with a round of 71, while South African Bregman had been on course for the outright lead until a bogey on the 14th.
The trio sit one shot clear of Wales' Tara Davies, who went round in 72, while Caudal is level with Italian Diana Luna at one under par.
Laura Davies, hunting an 80th career title, recovered from an opening round 74 with a 70 to sit three shots off the lead.
Collated second round scores & totals in the Ladies European Tour, Aberdeen Asset Management Ladies Scottish Open presented by EventScotland, Archerfield Links, East Lothian, Scotland
(Par: 72)
141 Florentyna Parker (Eng) 72 69, Carly Booth (Sco) 70 71, Stacy Lee Bregman (Rsa) 71 70
142 Tara Davies (Wal) 70 72
143 Diana Luna (Ita) 70 73, Anne-Lise Caudal (Fra) 67 76
144 Laura Davies (Eng) 74 70, Becky Morgan (Wal) 74 70, Lee-Anne Pace (Rsa) 70 74, Elizabeth Bennett (Eng) 73 71, Melissa Reid (Eng) 70 74
145 Sophie Giquel-Bettan (Fra) 73 72, Karen Lunn (Aus) 74 71, Rebecca Hudson (Eng) 73 72, Rebecca Codd (Irl) 70 75, Helen Alfredsson (Swe) 70 75, Stacey Keating (Aus) 73 72, Sarah Kemp (Aus) 69 76, Felicity Johnson (Eng) 74 71
146 Catriona Matthew (Sco) 74 72, Veronica Zorzi (Ita) 71 75, Frances Bondad (Aus) 71 75, Trish Johnson (Eng) 71 75, Margherita Rigon (Ita) 75 71
147 Gwladys Nocera (Fra) 72 75, Cassandra Kirkland (Fra) 71 76, Caroline Masson (Ger) 74 73, Nikki Garrett (Aus) 74 73, Lynn Kenny (Sco) 70 77, Heather Macrae (Sco) 72 75
148 Louise Larsson (Swe) 76 72, Kiran Matharu (Eng) 73 75, Danielle Montgomery (Eng) 74 74, Linda Wessberg (Swe) 72 76, Sophie Walker (Eng) 76 72, Caroline Afonso (Fra) 72 76, Rachel Jennings (Eng) 73 75, Tania Elosegui (Spa) 76 72, Bree Arthur (Aus) 73 75, Kylie Walker (Sco) 74 74, Becky Brewerton (Wal) 74 74, Giulia Sergas (Ita) 75 73, Vikki Laing (Sco) 76 72, Pernilla Lindberg (Swe) 74 74, Virginie Lagoutte-Clement (Fra) 74 74
149 Carin Koch (Swe) 77 72, Louise Stahle (Swe) 76 73, Georgina Simpson (Eng) 73 76
150 Hannah Jun (USA) 69 81, Lucie Andre (Fra) 75 75, Lindsey Wright (Aus) 75 75
Missed the cut:
151 Holly Aitchison (Eng) 74 77, Beth Allen (USA) 76 75, Anja Monke (Ger) 76 75, Ashleigh Simon (Rsa) 76 75, Kym Larratt (Eng) 73 78, Malene Jorgensen (Den) 77 74, Rebecca Artis (Aus) 72 79, Marianne Skarpnord (Nor) 71 80, Julie Greciet (Fra) 76 75
152 Stefania Croce (Ita) 75 77, Lotta Wahlin (Swe) 73 79
153 Jade Schaeffer (Fra) 74 79
154 Janice Moodie (Sco) 79 75, Ursula Wikstrom (Fin) 77 77
156 Jaclyn Sweeney (USA) 79 77, Nicole Gergely (Aut) 78 78
158 Lynnette Brooky (Nzl) 78 80
159 Zuzana Kamasova (Svk) 81 78
161 Gemma Webster (Sco) 81 80
