Tennis sensation Chung Hyeon has become the first Korean player to crack the top 20 of the ATP world rankings.<br /> The 21 year-old was up four spots to 19th in the latest singles rankings released on Monday.<br />It makes him the top-ranked Asian player in the world.<br />Chung is on a hot run at the moment,... reaching at least the quarterfinals in each of his past six ATP Tour events and making the semifinal of the Australian Open. <br />
