HONG Kong's top duo, Sam Wong Tak-sum and women's world champion Lee Lai-shan, begin their showdown for the Mobil Hong Kong Circuit crown at Shek O Beach today. The regatta is the fifth leg of the six-event domestic series, but the last for the pair and their national squad teammate Ken Wong Hop-hi. The trio will miss the final race at Stanley on December 4-5 as they will be in Auckland, New Zealand, for the World Cup. Sam Wong currently tops the table with two wins and one second-place finish and a victory at Shek O would secure him the overall title for the third straight year. However, Lee is breathing down his neck in second position overall with one win and two seconds. The 23-year-old Lee has been in outstanding form this year, winning three out of four major European regattas in the early summer and clinching the world and Asian titles last month. Lee proved she can hold her own against the male sailors by winning the fourth leg of the local circuit in Tuen Mun two weeks ago and posing a threat to Sam Wong for the overall championship. A victory this weekend could see her overtake Sam Wong for her first Hong Kong circuit crown. The only other sailor with a chance of overhauling Sam Wong and Lee to become the official Hong Kong number one is Tai Po-based Tang Luen-chun, who is currently in third place.