LONDON: Sweden's Robin Soderling, the player best-known for being the first man to beat Rafael Nadal at the French Open, has retired from professional tennis because of a long-running illness. The 31-year-old, twice a runner-up at Roland Garros, has not played an ATP World Tour event since 2011 due to mononucleosis, an energy-sapping viral illness. 'Thank you so much for all your kind words. So sad I won't play professional tennis again, but reading all your msgs makes me feel a lot better,' Soderling said on his Twitter account. Soderling spent 10 years on the Tour and rose to world number four. In 2009 he ended Nadal's domination in Paris with a stunning victory, only to lose to Roger Federer in the final Federer's only title at the claycourt grand slam.