Lorena Ochoa climbed into a two-stroke lead after carding a seven-under-par 65 in the opening round of the Master Card Classic in Mexico.
The world number one enjoyed a faultless round at the BosqueReal course while adding five birdies and an eagle three on the par-five ninth.
Ochoa leads Choi Na-yeon after the South Korean shot a five-under 67 while Americans Brittany Lang and Pat Hurst and Yani Tseng from Chinese Taipei are tied third after carding 68s.
Seven players are tied for sixth at three under.
Defending champion Louise Freiberg had a round to forget as the Swede shot a nine-over-par 81 while Briton Laura Davies endured a round littered with bogeys to return to the clubhouse at three over par.
Ochoa is chasing her second title of the season having captured the Honda LPGA Thailand at the start of the month.
CREAMER TIED AT TOP AFTER 67
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