TEENAGE tennis star Willy Chan Lee pulled off a major upset at the Asian Junior Championship in Singapore with a convincing straight sets triumph over top-seeded Taiwanese Weng Tzu-ting in the girls' draw. Willy, who is 561st in the world after turning professional for only 15 months, went into the match as the underdog as Tzu-ting is 231 places above her on the ranking list. The 16-year-old Hong Kong champion was in complete command in their quarter-final tie and clinched the match 6-2, 6-2. However, the Hong Kong Sports Institute scholar met her match in the semi-finals. She was beaten by South Korea's Jeon Hee-ra. Willy gave up schooling in late 1992 to pursue a career on the tennis circuit and quickly made her mark in the professional ranks with some solid results in regional satellite tournaments. She suffered an ankle injury in Australia last month, forcing her to miss the Nokia event - China's first professional tennis tournament for women. Singapore is only her second competition since the injury. Coach Mark Bailey is happy with the effort and is charting her return to professional tournaments next month.