Rafael Nadal is the biggest hard worker I have ever seen, says John McEnroe

In an interview to ABC.es the seven-time Grand Slam winner commented on injuries. The Spaniard often overcome physical issues thanks to his amazing fighting spirit, which was praised by McEnroe.

I could not give any suggestion to Rafa! He plays with an intensity which I thought was impossible. I never saw someone working so hard, said McEnroe. Nadal knows his body, he knows that he made a lot of effort.

Stopping and coming back is tougher for him. And he cannot really change his gamestyle. I am sure that its very frustrating seeing that he seems to be at 100% and he is not. In Australia last year it seems he was doing great, but then retired against Cilic in the quarters.

You do not expect it. Then he did not play for two months and he cameback winning all the clay-court tournaments. At Wimbledon he was looking good, but then he injured himself at the US Open again. Its unpredictable.

On the Australian Open predictions, McEnroe added: The Australian Open is the most unpredictable tournament because, for example, the players health plays a factor. Like we saw with Andy Murray. Or Nadals question mark.

But Djokovic always had a great success in Australia, six titles, and the way he ended the year its difficult not to say that he can win and keeping the No. 1 spot. Roger Federer seems prepared too. Its hard to pick. And then you see the younger guys.

One of them will breakthrough by the end of the year. ALSO READ: Djokovic would beat Roger Federer in Australian Open final – Evert