Former Swedish tennis star Robin Soderling has revealed that, according to him, a peak Novak Djokovic has a higher ceiling than Roger Federer at his best. Both the Swiss and the Serb are two of the greatest the world has ever produced, but Djokovic supposedly edges the grade when the two are pitted against each other.

Djokovic has struggled for form since winning the French Open in 2016 and lost his number one ranking to Andy Murray the same year. He managed just two titles this year and parted ways with his entire coaching team, including long-time coach Marian Vajda, ahead of the French Open in 2017.

The Serbian has not played since his loss in the quarter-finals at Wimbledon earlier this year and will return to action for the first time at the Qatar Open in Doha during the first week in January. He had ended his 2017 campaign prematurely due to an elbow injury.

Federer, on the other hand, had his best season in years, winning seven titles, including two Grand Slams – the Australian Open and Wimbledon.

Soderling has also backed Federer to successfully defend the Australian Open in 2018 ahead of archrival Rafael Nadal. The Swiss ace clinched the title this year after beating Nadal in the finals, overpowering the Spaniard in a gruelling contest.

"I always had tough matches against Roger. Playing against Djokovic, Nadal, I could go off the court and feel I played well. But against Roger, he just made me play bad," Soderling told Tennis Smash.

"Hmmm... but if they are both at the top, I think Novak would beat Roger more times than the opposite. He moved so well, got so many balls back. That's really tough for Roger because he might play too fast, he would panic a little bit. But it's really tough to say."

The duo of Nadal and Federer will not have their way in 2018 as they will have to contend with the return of many injured stars, such as Djokovic, Murray, Stan Wawrinka, Kei Nishikori and Milos Raonic, all of whom are reportedly confirmed for the 2018 Australian Open.

Novak Djokovic
Novak Djokovic has not competed since his quarter-final exit at Wimbledon this year Getty
Roger Federer Novak Djokovic Rafael Nadal