A simple oversight cost Karrie Webb dearly on Friday as she was disqualified from the Australian Ladies Masters for signing an incorrect scorecard.

The world No.8 and defending Ladies Masters champion shot a two-over par 75 in her second round at Royal Pines on Friday but signed a card which had her scoring a one-over 74.

The missing stroke was from a bogey on the par-5 12th which had been marked down as a par on Webb’s card, the eight-time Ladies Masters winner only realising the error after she had left the recording area.

It’s assumed Webb, who thought she was two-over for her second round, only remembered the course had changed from a par-72 to par-73 too late.

It ended a frustrating day for Webb who had hovered just above the cut line for most of her round, well behind leaders Cheyenne Woods (67) and Stacy Lee Bregman (67) who are both one shot clear on 10-under.

Ladies European Tour tournament director Fraser Munro said it was Webb herself who had brought the error to official’s attention before she flung her clubs into the back of a 4WD and drove away from the course in an obvious huff.

“Golf being a game of integrity, she did the right thing, came straight away and brought it to our attention,” Munro said.

“Initially she just wanted to get to the bottom of the problem. I think as soon as we established she had a five on her card (at the 12th) she was obviously upset.

“She’s the defending champion this week. She’s now not going to be able to go on and defend. She’s quite capable of low scores at this course and she’ll be extremely disappointed.”

Webb’s drama overshadowed the morning efforts of Woods and Bregman, who both went six under for the day to take the lead.

For 23-year-old Woods, the niece of superstar Tiger Woods, her highlight came with a eagle from the fairway on the par-4 1st.

“I knew I hit it really well,” Woods said.

“I knew it was the right club, good distance. I saw it land and then I looked away and they said ‘it went in, it went in’ so it was definitely exciting.”

Bregnall’s round came despite the 27-year-old snapping her eight iron when she struck a tree during her swing on the first hole.

She said keeping a cool head and adjusting her strokes to make up for the absent iron enabled her to get through the round.

“I was a bit upset but I never threw my toys out the cart or anything,” Bregman said.

“I always said when the situation comes to hitting that shot, if I needed the eight-iron you just got to work around it.

“It wasn’t really a big deal today.”

The pair lead by one shot from English veteran Trish Johnson, who shot a seven-under 66 to move into third while countrywoman Charley Hull also carded a seven-under 66 to move three shots off the lead.

Amateur Minjee Lee is the highest-ranked Australian at six-under for the tournament after carding her second straight three-under 70 for the tournament.