HONGKONG'S Ian Rayson faces a strong international challenge as he defends his men's division title at the Puma International Triathlon on Cheung Sha Beach in Lantau on Saturday. Rayson, who finished second in last Sunday's Singapore Triathlon behind world junior champion Spencer Smith of Britain, is favourite to lift this year's title over an Olympic distance which comprises a 1.5-kilometre swim, 40-km cycle and 10-km run. The 30-year-old ex-Royal Air Force engineer should be hard pressed by Taiwanese number one Charles Yu, Malaysia's Muhamad Razani-Husain and Singapore's Robbie Lindsay. Rayson, Razani and Lindsay last competed last October at the Singapore Long Course triathlon which produced some dramatic results. Razani won the race but only after Rayson, who was leading in the cycling segment was knocked off his bike, limping home with a leg injury for fourth place. Fast-improving Abelardo Alon-alon of the Philippines, Taksin Bornsoot of Thailand and Singapore's Kenneth Ng should be prominent early in the race but are not expected to finish in the money. Hongkong's Tony Wu Ka-fai can also be expected to be up with the leaders after his performance at last month's Arafura Games in Darwin when he finished sixth behind world champion Brad Bevan. Hongkong Sports Institute's scholarship triathletes Wan Shu-wah and Tony Chiu Kam-tong and the territory's other leading competitors, Alan Wilson, Lawrence Steel and Con O'Kelly are also expected to do well. There are no international entrants for the junior race but Hongkong can boast of having four of Asia's top six junior triathletes. Brian Bozarth, Don Bozarth jnr, James Hartwright and Cheung Man-ho should shine. Hongkong's top female triathlete, Ruth Hunt, ranked second in Asia, should easily win the women's event. Hunt's closest rival is expected to be Hongkong's Sue Ross, who showed good form by winning last Sunday's Singapore Triathlon. Kim Isherwood, the territory's other ''iron-maiden'' has opted to compete in the Saipan International Triathlon which will be held over the same weekend. Veteran triathlete Don Bozarth will be returning to the fold after a cycling accident in April, 1992 which almost wrecked his career. It will be a personal challenge for Bozarth, who was left hospitalised with spinal cord damage after a collision with a mini-bus. Bozarth and Mike Law, both of whom have won international veteran titles, will compete against Chan Chee-seng of Malaysia and Hongkong's James Stewart.