Ryu (66-61-69) will take plenty of confidence going into today at 20-under knowing she has plenty of experience of dominating the big days - just as she did last year in winning the US Open.

The 21-year-old, who posted a scorching 11-under 61 on Friday, admitted fatigue played a part as she was unable to replicate her magical round.

``My shot was not great today,'' Ryu said.

``My body was tired, (shooting 61 on Friday) took a lot of energy.''

Gritty Dutchwoman Christel Boeljon (66-65-68) matched Ryu's last hole birdie to finish on 17 under, losing no admirers as she chipped away at Ryu's lead all day to finish three shots back.

Ryu looked to have the Masters at her mercy on Friday after posting a career low 61 to jump four shots clear of her rivals.

Her 12 birdie round was hailed one of the best seen at Royal Pines, putting her in a perfect position to attack seven-time winner Karrie Webb's 2010 tournament record total of 262.

Webb's 26-under record is still possible if Ryu goes low on today and wins.

Yesterday was moving day and while Ryu didn't stall, several players made good ground on her.

What was significant however was the way Ryu finished - birdie, birdie - a reminder to those chasing her she is not going to give the tournament up.

The landscape however has certainly changed heading into the final round.

Yesterday she started 17-under and four clear of Boeljon with a gap of seven shots to Australia's Nikki Campbell and Korean Bo-Me Lee in third place.

Today she sets out three ahead of Boeljon with Korean Ha-Heul Kim, who eagled her final hole in her eight-under 64, and dangerous Italian Diana Luna (71-64-66) only four back.