By John O'Brien SINGAPORE (Reuters) - Yani Tseng had the golfing world at her feet during a glorious five-year spell from 2008 that saw the Taiwanese pick up five major victories and top the world rankings for 109 consecutive weeks. Following her 15th and final LPGA Tour victory in March 2012, Tseng began to second-guess herself on the course, her form disappeared along with the ever-present smile and the barren run saw her slip to 90th in the world just two weeks ago. On Thursday, Tseng was brilliant in the first round of the HSBC Women's Champions event in Singapore, her six-under 66 earning her a tie for first place alongside South Korea's Park and two strokes clear of Ko. "Oh, it's fun... it's so much fun," Tseng told reporters of her resurgence. More...