Rafael Nadal backed to see off Roger Federer and Novak Djokovic challenge in 2018

Nadal became the oldest player to finish the year number one after he clinched it at the Paris Masters.

Pablo Carreno Busta has backed Rafael Nadal to fight off challenges to his number one ranking in 2018 despite Andy Murray and Novak Djokovic returning to action to add to the already present Roger Federer, who will again vie for the top spot in men's tennis.

The Spaniard saw off the challenge from his long-time rival Federer to seal the year-end number one ranking in the penultimate event of the season – the Paris Masters – and will hope to maintain his spot at the summit of the ATP rankings in 2018.

Murray and Djokovic endured injury-plagued campaigns in 2017 but are set to return for the start of the 2018 campaign. They are certain to want to get back to the top – the duo started the year as the No 1 and 2 ranked players respectively - and will join Federer as the three main challengers for Nadal's spot at the top.

Fellow Spaniard Carreno Busta, however, believes that the 16-time men's singles Grand Slam champion can see off the challenges from the trio and finish another season as the top ranked player provided he is "hundred percent" fit.

Nadal's dreaded knee injury resurfaced in the final months of the current campaign, forcing him to pull out of his first Paris Masters after two matches, and then the ongoing ATP Finals in London after his first round robin match, which he lost to David Goffin.

"And me, no?" Carreno Busta said with a smile when asked if Nadal can defend his No 1 ranking when Djokovic and Murray return next season, as quoted by the Metro. "No, Rafa is a really great player."

"He's one of the best players in the world. He can do everything, no?

"You never know. If physically he's at hundred percent, he can finish the season again No 1," the Spaniard added.