Sung Hyun Park got to six-under through 14 holes before play was halted by darkness in the weather-delayed first round of the abbreviated LPGA Texas Classic on Friday.
After Thursday's play was cancelled and Friday's began after an 8-1/2-hour rain delay, the tournament was reduced from 72 holes to 36.
There will be no cut, but only the top 70 and ties in the 144-woman field will win prize money.
Su Oh is the best-placed Australia, making three birdies through 10 holes to be three-under-par.
Park, last year's US Women's Open champion and the top-ranked player in the field at No. 5, had seven birdies and one bogey to top the leaderboard at the 6,475-yard Old American Golf Club, which is hosting the event for the first time.
Half the players did not start their first rounds.
Last week's winner Lydia Ko and another former No. 1, Ariya Jutanugarn, were at two under through 14 holes, as was Hall of Famer Laura Davies.
