PARIS (REUTERS) - He might have arrived in Paris in great shape, having lost only one match on clay this season, but Rafa Nadal is still wary of the threat posed by his French Open first-round opponent, the unpredictable Benoit Paire.

Although he has often wasted his talent with his antics and his inability to handle frustration, Frenchman Paire is a gifted player anyone should handle with care, nine-time Roland Garros champion Nadal said.

"He is not an opponent you want to play against in the first round," Nadal told a news conference on Friday (May 26).

"A player with big talent. Great serve, great hands. Fantastic backhand, no? He is a dangerous opponent. Yeah, that's it. I need to play my best."

Nadal, whose last title in Paris came in 2014, has again become the favourite after struggling with form, reaching his first grand slam final in three years at the Australian Open in January.

He went on to win three of the following four claycourt tournaments he has entered, only losing to Dominic Thiem in Rome.

"It's true that since the beginning of the season, I am happy the way that I played. I think I play well in almost every event that I have been in," said Nadal, who turns 31 next month.

"I played well on hard. Then played great on clay. Happy about the events that I won. Three events I have won have been very important for me," he added, referring to the Monte Carlo, Barcelona and Madrid titles on his favourite surface.

The Rome defeat against Thiem did not worry Nadal, who said it came at the end of a long series of matches.

"In Rome, I was a little bit tired mentally more than physically, because it was a lot of days in a row playing at high intensity," said Nadal.

"Now I am very tired because it's very, very warm here," he joked.

"But that's it. No, no, I am very happy the way that I arrived here. Now I have to play well here. That's all."