Sorenstam played a steady round in tough conditions

Going into the final round at DuPont Country Club in Delaware, also being played on Sunday, Sweden's world number one was on seven under par 206 after her one-over 72 .

South Korea's Han Hee-won, who had a 74, and Kate Golden, an American who made a hole-in-one at the 17th in a 68, were her nearest threats on 210.

Sorenstam, who had to complete 15 holes of the third round, said the days of heavy rain had left the course almost unplayable.

"I'm very surprised that we managed to play today and it is still extremely wet," she said between rounds. "But all credit to the green staff, they did a great job."

She added: "I'm feeling good and very happy with my position going into the last 18."

Dropped

Sorenstam was tied with Han, seeking a first win in her third season on the Tour, when play was stopped in torrential rain after three holes of her third round on Saturday.

But with the South Korean taking a double-bogey at the sixth, she moved into a lead that she continued to stretch.

She moved four clear with a 6ft birdie at the short 17th, and would have been even further ahead if she had not dropped a shot at the last where Han also took bogey.

Golden has never had a top 30 finish in 10 years playing in majors, and the highlight of her three under par round was the ace at the 155-yard 17th where she holed her eight-iron tee shot.