Sports like Tennis are as much of a mind game as they are pure athleticism. No one knows this better than Oakley International Tennis Star Janko Tipsarevic. He recently revealed his three toughest opponents. And not surprisingly, he’s really, really close to one of them. Janko is currently raging into the semifinals at the AEGON International 2011 in Eastbourne after topping Grigor Dimitrov of Bulgaria in straight sets 6-3, 7-6(2). He’ll take on World No. 59 Kei Nishikori of Japan next.