Over the past couple of seasons at the game's biggest events, Novak Djokovic and Rafael Nadal have consistently booked their places in the finals. Heading into Wimbledon this week, they've met in four consecutive Grand Slam title rounds, with Djokovic winning three of the encounters.
They're poised for more of the same at Wimbledon, where between them, they've won three of the last four titles. However, when they return to the All-England Club a few weeks later for the Olympics, they'll be hard-pressed to square off in the gold-medal match. Here's a look at some obstacles that might be too much for them to overcome.