Lleyton Hewitt has recently commented on Roger Federer and Rafael Nadal potentially continuing to dominate the world of tennis in 2018.

Following another impressive year for both men, like many of us, Hewitt is unsure if the two are actually human when asked if Federer and Nadal can keep challenging at the major tournaments throughout 2018.

"You wouldn't think so, but I don't know if those two are normal, especially Roger," the 36-year-old said, as per The Express.

"At his age, he's wound back the clock.

“Even against Rafa, he's done the best he ever has against him.

"I wouldn't say there's anything those two can't do."

Federer is actually the same age as fellow former world number one Hewitt and the latter can certainly relate to the aches and pains the Swiss star would have experienced over the course of another gruelling season. 

Nevertheless, the way he has managed his workload in 2017 to peak at the Grand Slams means Hewitt is backing his old rival to claim a sixth Australian Open title once the new season gets underway.

"Federer has been so dominant, especially in big tournaments. He's gonna go in - even at the age of 36 - as probably the favourite.

"Especially the way Nadal obviously had to pull out of London.

“But there’s going to some opportunities for some young guys to stand up and maybe win a grand slam.”

Nadal had to pull out of ATP Finals in London earlier this year due to a knee injury that plagued him before the tournament, however, it is rumoured he will return to action this month in Abu Dhabi.

The 31-year-old goes into 2018 ranked No.1 in the world, even though he suffered defeat to Federer three times this year. 

And you can guarantee the Spaniard will be using that as motivation if the two meet once more in Melbourne Park.

The latest edition of the Australian Open will get underway on January 15.