The early rounds of tennis this year have proven especially volatile, and this year’s U.S. Open has so many dramatic story lines that you may want to be there from the start – and you can, by tuning to Tennis Channel at 11 a.m. ET for eight hours of first-day live coverage, or, from 1-6 p.m. ET, five hours on ESPN. Among the main stories: Novak Djokovic, after a dramatic Wimbledon win against Roger Fededer, tries to reach the finals here, with persistent rival Rafael Nadal sidelined with a wrist injury. Serena Williams hopes to earn her third U.S. Open title here, reversing a very shaky year. And Eugenie Bouchard, the 20-year-old Canadian, has been coming on strong, but not as strong as Petra Kvitova, who beat her in the most recent Wimbledon women’s final. And then there’s Maria Sharapova, coming back from injury. Lots of drama – and, on the women’s side, lots of grunts.