John McEnroe's argument with Rafael Nadal and why he prefers Novak Djokovic

As prepares to retire from , many fans may remember his indirect exchange of words with the great . Nadal, 38, will retire from the sport when his country's Davis Cup campaign comes to an end.

The Spaniard has admirers all around the world, many of whom consider him to be the greatest player to ever pick up a racket. McEnroe, who is an icon in the sport himself, will be one of many tennis legends who will also have nothing but good things to say about the 22-time Grand Slam winner.

Yet, the American once found himself in an awkward exchange of words with the Spaniard after he insinuated that Nadal would repeatedly overstep the sport's shot clock, which gives players 25 seconds between points to serve. When Nadal heard about the comments, he served back at McEnroe in intense fashion.

On commentary, McEnroe said Nadal takes 30 seconds to serve instead of 25 and said he gets away with it because he is "that great". When he was pitted with McEnroe's comments, a perturbed Nadal said: "I am following the rules. If I am having more than 25 seconds I receive a warning every single time. If not, check the clock. I don't think I'm receiving different treatment at all. I don't understand why John can say that on the TV, but I am going to have a chat with him later."

An even more frustrated McEnroe then said: "Why did they throw me under the bus? We haven't had that talk (with Nadal) but let me just add that... he didn't let me finish, whoever the dumb journalist was. Rafa Nadal is entitled to do whatever the hell he wants, that's part of why you get as good as [Nadal is], you've got to deal with that.

"And it's not up to him. We all know that he's been doing this for the past 10 to 15 years. There's nothing new to that. It's not his call - it's the umpires."

It's presumed that the minor hatchet between the pair was eventually buried. While their brief quarrel will not have any effect on his thoughts, McEnroe has most recently said he thinks Novak Djokovic just about edges Nadal when it comes to competing on grass courts.

When previously asked about his choice betweeen Nadal, Djokovic and Roger Federer on the surface, McEnroe said: "At the moment for me, Nadal is the greatest player that has ever lived on clay. Novak would be the same on hard courts. Roger on grass, even though Djokovic has beaten Roger a few times at Wimbledon."

He also said he admires the way Djokovic can feed off a hostile crowd or people trying to write him off. He added: "Djokovic rises to the occasion. He needs to get inspired or have someone write him off. Some type of chance to break an amazing record.

"No one is writing Djokovic off. Sometimes his attitude on the court fuels him. You'd rather be respected than loved. You'd rather have both if possible, but he's handled it well. He has been mature about it and he's been pretty successful turning lemons into lemonade.

"Even when people were getting on him, for calling on the trainer for example, it's almost like people are looking for an excuse to get on him. I can relate to that. I deserved it more than he did. It's not easy to take that to use it and fuel you. To me, he's better than anyone at that to ever play the game."