At first glance, it is the classic story of the sporting prodigy that burns twice as bright and half as long. Lydia Ko was the young golfer who performed more as a teenager than anyone in the history of the sport. She already won professional tournaments at the age of 14 and became world number 1 in 17, four years younger than Tiger Woods in the men's competition. Even now, with 15 wins from the LPGA Tour and two major titles under its belt, the New Zealander is still only 21.