FO Day 6 (3R): Djokovic-del Potro match stopped at a set a piece due to darkness
As the hour headed to about 7 PM, there was a battle brewing on Court Philippe Chatrier. The ESPN announcers astutely observed that if Tsonga didn't win the match in straight sets, he would lose in 5 sets. The reason? Stamina. Tsonga, like his countryman Monfils, is susceptible to injury. When you're injured, it can

