John McEnroe believes Novak Djokovic is capable of beating Jannik Sinner at Wimbledon this afternoon, despite 'uncertainty' surrounding the Serb. Djokovic has been in fine form at the All England Club this summer,

John McEnroe says no one from the current group of players understands Wimbledon's grass better than Novak Djokovic, and considering that the green stuff is not Jannik Sinner's top surface, the American tennis icon is backing the Serb to beat the world No.