Novak Djokovic admitted on Sunday he will miss injured rival Roger Federer as he prepares to begin his charge for the Dubai Championships. Swiss defending champion Federer was forced to withdraw after this week undergoing right knee surgery which will reportedly keep the 20-time Grand Slam winner away until the summer grass season. "It was a surprise, to be honest," Djokovic said prior to his Monday start against Tunisian wildcard Malek Jaziri. "I knew he was struggling with an injury in the Australian Open. But no one knew really what was the...