At 8-under-par for the tournament, she leads by four shots over Rosie Jones, Rachel Teske and Wendy Ward, all of whom sit at 4-under.
That margin could have been much more, however.
For a while on Saturday, it appeared as if Andrews might join Annika Sorenstam as the second player ever to break 60 in an LPGA Tour event.
It surely appeared that way after she reached 9-under for her round after birdieing the par-4 15th, as the easy par-5 16th ahead.
But Andrews would come undone.
After driving her ball in the right rough, she elected to lay up, but instead hit a weak duck hook to the left side of the fairway. Then on her next shot, Andrews played a 7-wood, but hit a banana slice way right.
The end result was a bogey-six, dropping her back to 8-under for the round.
Amazingly, she came back with a vengeance on the next hole, pouring in a 30-footer for birdie and getting back to 9-under, but then things got a little strange on the finishing par-4 18th.
Seemingly in with a four, after having tapped in her par putt from two feet away, Andrews called a one-stroke penalty on herself, claiming she had double-hit the final tap-in.
As it was, the round was brilliant regardless.
Four strokes ahead, Sunday will mark the ninth time that Andrews will enter the final day of a tournament with the lead. She has yet to win since 1998, however.
Day 2 was met with much calmer conditions than the 30 mph winds from the opening round.
Yet, while overnight leaders Gloria Park and Kelly Robbins were the only players to shoot 68 on Friday, they each fared worse on Saturday.
Park shot 69 to end in a tie for fifth at 3-under, while Robbins carded 71 to fall to eleventh.
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