Rafael Nadal is known as the "King of Clay" and it's not for his pottery skills.
The 16-time grand slam champion has won an unprecedented 10 French Open titles and is odds-on favorite to win an 11th.
Spaniard seeks 11th French Open title
Nadal has only lost twice in Paris
Pat Cash and Mats Wilander give their views
No player in history has won as many grand slam titles at a single tournament.
The Spaniard won the French Open on his debut as a 19-year-old and came into this year's event with a 79-2 win-loss record at Roland Garros.
Recently, he compiled a remarkable streak of 25 straight victories on clay and also set a record of 50 consecutive sets won on a single surface.
But what makes the greatest clay-courter of his generation so good on the slow red dirt?
Former grand slam winners Pat Cash, Mats Wilander and Yannick Noah talked CNN Sport through the Mallorcan's game.
"He's unbelievably fast, and he can keep going forever, which helps on the clay," Australia's Cash, the 1987 Wimbledon champion, said in an interview at Roland Garros.
"He keeps getting the ball back, his speed and athleticism is just phenomenal.
"His footwork on the clay is amazing, I don't think I've ever seen anybody move that quick on the clay."
Nadal's technique also sets him apart.
"We have never seen a player hit so much top spin before," said Cash, who now coaches American Coco Vandeweghe.
"The power he puts into the shots and the top spin is just very, very hard to control on a slow court over five sets.
"The quicker the courts get, the harder it is going to be for him to actually create that top spin and the ball skidding through.
"But when he has a little bit of extra time, and he can move back further and give himself more time to hit, he's able to hit the ball with more spin, which enables the ball to bounce higher and push the opponent around."
In addition to his technical abilities, Nadal's mental strength is what truly sets him apart from the rest of the field.
"Mentally, he's just ferocious," Cash said.
"Clay is one of the toughest surfaces to be successful at, because you have to be focused all the time, the momentum can change very quickly.
"On grass or other courts, you can hold your serve, or hit a couple of big serves and stay in it, but not on the clay, you have to be persistent all the time."
For Nadal to lose at Roland Garros for only a third time, three things need to happen, according to three-time French Open winner Wilander.
"Rafa has to play somebody he is intimidated by in terms of talent, it has to be a rainy, wet day here at Roland Garros and Rafa must not play very well," the former top-ranked Swede told CNN in Paris.
Nadal excels when it's hot as his heavy top-spin shots kick up high -- rain tends to dampen one of his main weapons, according to Wilander.
"With Alexander Zverev, I think we are seeing the building of the perfect player who could beat Rafa," he adds.
"He's tall, a great two-handed backhand, a big serve, a bit reminiscent of Robin Soderling, the tall Swede who beat Rafa here once."
Noah, the only French man since 1946 to win at Roland Garros when he beat Wilander in the 1983 final, says you have to think outside of the box to beat Nadal.
"I'd serve under arm and I'd hit only drop shots," he jokes in an interview with Cash for CNN's Open Court at Roland Garros.
"And if he's at the net I'd hit it at him. You have to try something."