Andy Murray and Novak Djokovic had a great 2016 while Rafael Nadal and Roger Federer were troubled with injuries. The tables turned in 2017 as Nadal and Federer were splendid, but Djokovic and Murray could not play impressive tennis. Hence, the year 2018 is going to be an interesting one, with all four players expected to be fit and start the year with a bang.

It could be anyone's year.

Nadal and Federer are currently ranked number one and two in the ATP rankings respectively. Djokovic and Murray have slipped down the rankings as they lie on 12th and 16th place.

One should not look too much into the rankings as Djokovic and Murray missed many tournaments in 2017.

Roger Federer and Rafael Nadal
Federer and Nadal- can they dominate in 2018?MICHAL CIZEK/AFP/Getty Images

There is no denying the fact that all these four stars can beat anyone on a given day, provided they are fully fit. The world tennis needs Murray and Djokovic to be on top of their game, which will make the men's tennis even more interesting.

Though Federer's former coach Paul Annacone is not aware of Djokovic and Murray's health now, he feels the duo will give Federer and Nadal a run for their money in 2018.

"I don't know how healthy Novak and Andy is but when you start playing three out of five sets especially with their style of play, where they don't get a lot of free points, they are working hard from day one, we are going to see how healthy they are early on," Annacone told Beyond the Baseline Podcast.

"And if they are healthy, they are great players. Great doesn't just stop, especially at their age. They are not all of sudden not great anymore.There's no reason why Djokovic and Murray can't be at the top of the game with Federer and Nadal next year."