The golf competition, which is usually called the fifth major on the men's side, was hit by a storm already during the opening day on Thursday and 47 players have not yet finished playing the first round.
Friday's rain break creates new worries for the organizer.
Two Swedes have completed the first round, Alex Norén on a nice 69 strokes, three under par, while Henrik Norlander went on an over par, 73 strokes.
Henrik Stenson has gone 13 holes in the first round and is one over par.
England's Tommy Fleetwood and American Tom Hoge are the best of those who have completed the first round so far, both in 66 strokes, six under par.