Big-hitting South African Nico van Rensburg fired a five-under-par 67 to take a share of the lead after the first day in the US$500,000 Omega PGA Championship at the Mission Hills Golf Club yesterday. The Philippines' Felix Casas joined Van Rensburg at the top of the leadership board, one stroke ahead of Australia's Kenny Bruce, Indonesia's Kasiadi, India's Amritinder Singh and Scotland's Simon Yates. Van Rensburg, a three-time winner on the Davidoff Tour, was delighted by his early success, attributing his low score to some intensive coaching sessions with compatriot Peter Bakker. 'I have been working very hard with Peter. I have been working on getting my weight through on to my left side better. 'It's stopped me from pushing shots, and it has really helped,' said the 33-year-old South African, ranked 21st on the Davidoff Order of Merit. Playing the back nine first as the 160-field was split into two sections, Van Rensburg, the Volvo Masters of Malaysia champion, had a string of birdies on the 11th, 12th, 13th and 16th before bogeying the difficult 464-yard par-four 18th, where he was plugged in a greenside bunker. His performance on the front nine was also consistent, gaining birdies on the sixth and ninth to fire himself into title contention. His birdie on the final hole was brilliant. He hit a five-iron 180 yards into the wind for his second shot on the par-four ninth to three feet. Casas also had a near faultless day as he put himself into title reckoning. Only a solitary bogey on the 17th tarnished an impressive display from the 33-year-old Filipino. 'My putting has been excellent. I like this course and I am familiar with it having played on the Johnnie Walker tour two years ago,' he said. Burma's Kyi Hla Han all but secured the Davidoff Order of Merit title after nearest challenger Gerry Norquist of the United States faltered after a disastrous round on the Jack Nicklaus-designed World Cup course. Han shot a two-under-par 70 to put himself in joint 10th position but most importantly, he is within a whisker of clinching the title. While Han mastered the course, Norquist left himself 10 shots off the pace after carding a disappointing five-over-par 77. Before teeing off yesterday, Norquist was the only player who could have overtaken Han for the Merit title but he needed to win at Mission Hills, with Han finishing no better than sixth. Han was four under after 16 holes before squandering chances of improving his round after three-putting the 17th and 18th holes. 'I wasn't even thinking about the Davidoff Tour Order of Merit. I was just thinking about this tournament,' Han, 38, said. 'I played really well and was four under until the 17th and 18th. I'm really annoyed at those putts.' American Fran Quinn, winner of last year's Mittweida Thailand Open, returned a 69 along with compatriot Clay Devers, Korean Anthony Kang, India's Arjun Singh, South African James Kingston, Japan's Daisuke Tsuchiyama and Taku Yamanaka, and Taiwan's Chung Chun-hsing. Defending champion Kang Wook-soon of South Korea carded a 70.