The 31-year-old LPGA Tour player, who was born in England but moved to South Korea at the age of four, birdied the 14th and 18th holes to finish.
She said: “I shot even today and it was pretty difficult reading the greens. Inside 15 feet I kept missing putts. I hung in there and I’ve got one more round.”
The 18-year-old Yang, who is a rookie on the Korean Ladies Professional Golf Tour, made her move over the front nine, which she played in 34. She came back in 37 and rued a missed birdie putt from 10 feet at the par-five 18th hole.
Touted as one of Korea’s future international stars, Yang is yet to win on the KLPGA and is 20th on the money list but with a win she could have a chance to become the Korean rookie of the year.
Yang said: “I feel very lucky because it was very difficult in the wind. Every single shot I was thinking about which club to hit because the wind was changing from upwind to downwind.”
Having started the day a shot behind the leader, Rawson was disappointed with her efforts but remained optimistic that this could be the week when she records her first victory in five years as a professional.
She was the outright leader after 12 holes, having birdied the first and 11th, but finished with four bogeys in a row to drop two shots behind the leaders.
“It started off well. I was hitting it great, playing well and hitting good shots,” she said, adding that she three putted the last three greens after her hands got cold and she lost her rhythm.
Coakley, who like Rawson, has ties to Adelaide, also started well but lost her momentum on the back nine.
She was two-under overall through 13 holes but double bogeyed the par-five 14th. She said: “I was going really well and then on 14, the par five, I hit a good drive, a good second shot, was in between clubs for my third shot and had a hanging lie. I caught it a bit think and it’s pitched just past the pin and it just goes straight downhill from there so it’s gone OB by about a foot. I took seven on that hole so that set me back a bit. I had the momentum going. I think it was a bit of indecision because I wasn’t sure what club and went with a little bit more and eased off it a bit. I caught it a little bit thin and on this golf course anything that goes long is OB. Asian golf courses are like that. I’m playing well. I just need to stop making so many bogeys.”
South Korean Eun Jung Sin had a hole in one at the 12th, but her 36-hole score of nine-over was just short of making the cut, which fell at plus eight. A total of 66 players will play the third and final round on Sunday, which begins at 9am local time.