Despite all his success this year, Rafael Nadal still hasn't sewn up the year-end No. 1 ranking. After coming back from a career-threatening knee injury to win 10 titles this year, including two Grand Slams, Nadal has clearly exceeded expectations. He overtook Novak Djokovic for the No. 1 ranking last month, although the Serb can reclaim it this week at the season-ending ATP World Tour Finals. ''I've already finished the year as the world No. 1,'' said Nadal, who finished on top in 2008 and 2010. More...