A birdie burst down the home stretch enabled  Italian Giulia Sergas to hold a two-shot lead at the halfway point of the Pegasus New Zealand Women’s Open at the Pegasus course today, although her overnight lead has been pruned by a shot. Sergas looked vulnerable after successive three-putts on her ninth and 10th holes resulted in her dropping a shot – she was putting for eagle on her ninth hole, the par-5 18th – and  she dropped back to her overnight score of eight-under, a shot adrift of Australian Kristie Smith.But the experienced Sergas, a professional for 11 years, rediscovered her touch after her bogey on her 10th hole (the course’s first hole) and reeled off four straight birdies from the fourth to the seventh to rocket to 11-under.She said it had been `a nice walk in the park’ until the two three-putts happened. “I thought I can do better than this. Some putts lipped out but I stayed calm – there was some love for me. I knew it was going to be a hard day for me so I stayed humble,’’ Sergas said, adding that she was feeling better after a bout of the flu.Sergas, despite six top 10 finishes, is still seeking her first win, but she is well-placed going into the weekend money rounds. Smith, who had nine birdies and a three-putt bogey at the 15th in her eight-under 64, is alone in second place at nine-under, two better than Swede Linda Wessberg, who equalled the course record of 63 with a round that had 10 birdies, seven of them in a row from the first hole (her 10th).The best of the New Zealanders was 13-year-old amateur Lydia Ko, who had a bogey-free 68 to finish on six-under and to be tied fourth with defending champion, Laura Davies (England), who made her move early in the day with a 66, Sweden’s Pernilla Lindberg, who had the same score in the afternoon, and France’s Cassandra Kirkland, who had her second 69.Northland’s Caroline Bon, who turned professional late last year, was the second best Kiwi tied for 10th at four-under while former New Zealand touring pro Liz McKinnon missed the cut but celebrated with a hole-in-one at the par-3 148m 14th hole.  It was her second ace, the first coming in the England Open three years earlier.The cut was at four over with 71 professionals and two amateurs – Ko and Auckland’s Cecilia Cho – to play the final two rounds.Smith, who turned professional in 2008 not long after claiming the Australian women’s amateur championship, had her maiden win in the paid ranks in the Royal Canberra Ladies’ Classic and last year she had her first success on American soil with victory in the Daytona Beach Invitational, a Futures tour event.The 22-year-old Western Australian was on course for her initial win on the LET (European Tour) last week after rounds of 67 and 65 at Royal Pines had her joint leader at halfway, but it turned sour over the last 36 holes and she finished tied for 23rd.“ This week I’m free-wheeling a bit more and not really caring as much. I get to go home Monday and I’m looking forward to that after not being there for quite a few weeks. I’m happy to have made the cut and I’m going to make a cheque,’’ Smith said, adding that she was without a regular caddy and was making her own assessments.“I’ve got a local caddy on the bag and he’s been great – he’s done exactly what I’ve told him and that’s to keep up and shut up. I’ve been doing my own yardage which is very different and that’s keeping my mind busy which is nice as it takes some of the anxiety out of the harder shots.’’