Novak Djokovic has achieved just about everything possible in tennis.

The world No. 1 is clear on the toughest task in tennis: Beating Rafael Nadal at Roland Garros.

Stan: Rather Face Novak Than Roger

Djokovic is the last man to beat the king of clay on the red clay of Paris posting a 7-5, 6-3, 6-1, sweep in the 2015 Roland Garros quarterfinals.

The top-seeded Serbian slammed Nadal in the Australian Open final in January to capture his 15th career Grand Slam title.

Djokovic, who can complete his second career Nole Slam by winning Roland Garros and holding all four majors simultaneously, says beating the 11-time French Open champion in Paris is the ultimate challenge.

"It would definitely be not too bad," Djokovic said when asked about beating the world No. 2 at Roland Garros. "Beating Rafa in Roland Garros would be and is one of the ultimate challenges of this sport as is winning against Roger (Federer) in Wimbledon.

"I have been fortunate enough to experience both, so it is quite a special feeling because they have dominated those surfaces so much in their careers."

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