Six -time champion Andy Roddick beats Kazakhstan 's Mikhail Kukushkin at the Centre Courts . Second seed David Ferrer also wins his opening match of grass-court event . second seed David Ferrer progresses along with three -time runner-up Andy Roddick . Former world No . 4 Juan Martin del Potro also reaches second round in Kazakhstan .
Six-time champion Roger Federer beats Kazakhstan 's Mikhail Kukushkin at Wimbledon . Second seed Novak Djokovic also wins his opening match of grass-court event . Seventh seed David Ferrer progresses along with three-time runner-up Andy Roddick . Former world No . 4 Juan Martin del Potro also reaches second round in England .