Rafael Nadal

The defeat of Rafael Nadal and Novak Djokovic, two of the big stars who were expected to reach at least the semi-finals of the Australian Open and the former's subsequent rant against the heavy workload on top players holds out worrying signs for the world of tennis. The recurring injuries to Nadal and Djokovic are not a good sign. The second and more important point is that these two are among the quartet -- the others being Roger Federer and Andy Murray -- who have won 50 of the last 55 Grand Slams showing how they have dominated men's tennis.