Sweden’s Cecilia Ekelundh also lay two shots off the lead on Australia’s Gold Coast, while six players were a shot further back on five under par.

Karrie Webb, the tournament favourite, had a disappointing 71 to finish the first day in joint 39th position with the defending champion, Amy Yang, 17, from South Korea and 17 other players.

England’s Laura Davies and Lora Fairclough were the next best-placed Britons. They both had three-under-par 69s to finish the day in joint 14th position while England’s Lisa Hall had a 70.

Brewerton, 24, of Abergele, is looking to secure her first victory this week at the beginning of her fourth year as a Ladies European Tour professional.

She has had a promising start to the 2007 season, finishing eighth in the Women’s World Cup of Golf and tied 17th in last week’s Women’s Australian Open.

Since last week, Brewerton has had Bosco Lynch on caddy duties, replacing her dad Steve who has been carrying her bag since her days as an amateur.

Brewerton admitted that it marked a new phase in her career.

“I suppose it is going to be different from always having someone there that perhaps I relied on too much. It is going to be different and it is like I’m starting again,” she said.

Brewerton’s father Steve, a popular character on the women’s circuit, caddied for Brewerton in the recent Women’s World Cup of Golf, his last official tournament on duty.

“It was about time that he went home and acted as a proper husband!” joked Brewerton.

“He was also getting a lot of injuries last year, aches and pains. He’s got arthritis in his hips and in his back so last year he struggled. He came out to South Africa for the World Cup, which was his last event and he was absolutely shattered at the end of that week as well. I think he’s looking forward to a bit of a break.”

Brewerton carded six birdies in her first round, with three on the front nine and three on the back nine.

She revealed that her first-round 66 was the result of working harder than ever on her game over the winter off-season at Desert Springs in Spain.

“I’ve done more and now I feel better and more prepared at the beginning of the season rather than feeling a bit rusty,” said Brewerton, who is currently tied for seventh place on the Ladies European Tour’s 2007 New Star Money List.

“I played pretty well last week. All my rounds were a bit upside down; lots of birdies and lots of bogeys. But I felt like I was close to playing really well and then today went really well.”

Ahn, the first-round leader, had 10 birdies and two bogeys for an eight-under-par 64.