Jennifer Rosales matched par last Saturday but found herself slipping down the leaderboard after 36 holes of the $1.3-million Navistar LPGA Classic in Prattville, Atlanta.

Rosales, on a mighty bid to regain her old form, failed to make a big follow-up of her first round 69 to slide seven shots off the leaders at 141. She is now tied with 12 others at 40th spot.

World number one Lorena Ochoa and 14-year-old US teen were among five co-leaders after Friday’s second round.

Mexico's Ochoa, the defending champion, fired a four-under-par 68 and Thompson, a ninth-grade schoolgirl trying to become the youngest winner in LPGA history, fired a 69 to stand on 10-under 134 after 36 holes.

Joining them atop the leaderboard were Britain’s Laura Davies, who fired a 65; Taiwan’s Yani Tseng, who matched a tournament record by firing a 63; and Italy’s Giulia Sergas, who fired a 65.

Sweden’s Sophie Gustafson, who won last week, fired a 65 to stand alone in second, one stroke back of the lead pack. Among those two off the pace are Britain’s Janice Moodie and US prodigy Michelle Wie, still seeking her first major stroke-play title.