The Australian, who famously defeated Nadal at Wimbledon in 2014 when he was aged just 19 and ranked 144 in the world, has still to get beyond the quarter-finals of a major.
And he thinks Nadal remains the overwhelming favourite to win a 10th French Open and take his personal majors haul to 15.
"I don't think he's worried at all about anyone in this tournament, to be fair," said the 18th-seeded Australian, who beat German veteran Philipp Kohlschreiber 6-3 7-6 (4) 6-3 on Tuesday to reach the second round at Roland Garros.
"Best of five, it suits him. He knows he's not gonna lose. Let's be realistic."
It was 20-year-old Alexander Zverev's triumph over Djokovic in the Rome Masters final which prompted whispers of an imminent shift in power at the top of the game.
But Kyrgios is not convinced that day has come, pointing to the contrasting fortunes of 23-year-old Dominic Thiem in Rome.
The Austrian stunned Nadal in the quarter-finals but managed to take just one game off Djokovic in the semis.
"I can't really see the changing of the guard happening any time soon because of one tournament," said Kyrgios, who is playing in Paris having suffered hip and elbow injuries which ruled him out of the Rome and Monte Carlo events this spring.
"I think the young ones have a way to go. Thiem played an unbelievable match in Rome to just beat him. Then look what happened the next round, he's completely gone.
"What don't I like about clay?. I don't like how my shoes get dirty. When I'm back home I don't really train that much on clay because it makes my cars dirty, too."