Third round play at the Portland Classic was called off because of wet conditions and forecast rain with the LPGA Tour later reducing the event to 54 holes.

The hilly Oregon Golf Club course was soaked with more almost 2 inches of rain overnight on Friday with course conditions and the forecast of more wet weather forcing the hand of organisers.

The LPGA Tour said tournament officials will monitor the course on Sunday morning, with the intention of beginning the final round at 7.30am local time in groups of three off the first and 10th tees.

While officials hope to finish the competition on Sunday, play may extend into Monday if necessary.

South Korea's Jin Young Ko holds a one-shot lead after two rounds at 8-under 136.

First-round co-leader Gemma Dryburgh of Scotland is second at 7 under while Spain's Carlota Ciganda, another first-round co-leader, is 5 under.

Su Oh is best of the Australians at 4 under in a seven-way share of fourth.