Madelene Sagström had up to the fifteenth hole on a swaying Saturday in Grand Rapids, with two bogeys and two birdies.
But the finish was all the finer, with three straight birdies.
That meant 70 strokes, two under par, and a split seventh place ahead of the decisive round.
One blow worse is still Anna Nordqvist, divided nine, who also went around 70 strokes.
Nelly Korda leads the competition in a total of -18, six strokes ahead of Sagström.
The American finished with an eagle on the last hole by lowering a putt from just over six meters, which meant 66 strokes on the round, six strokes under par.
- I just trusted my line and it went right in, but it was a perfect putt and it was great to hear the audience go completely crazy too.
It was really cool, says world runner-up Korda.