Montreal: Rafael Nadal says his mental stability has returned after a topsy-turvy year for the former world No. 1. The 29-year-old Spaniard arrived in Canada last week for the start of the North American hardcourt season, having picked up his third title of the year in Hamburg.

He will now hope to build on that as he attempts to claim a fourth Rogers Cup title, here.

"It's always about adapting your tennis," Nadal, beaten by lowly-ranked Dustin Brown in the second round at Wimbledon, said about the challenges in store over the next few weeks, leading up to the U.S. Open.

"There's a different way of hitting the ball, but at the end of the day it's tennis. Hamburg had been a positive week for me.

"Mentally I am stable now, something that I wasn't able to do very often this season. My mental powers have been up and down more. Hamburg was not the case and I'm working well," he said

Twice US Open champion Nadal, seeded seven, faces a potential quarter-final in Montreal with world No. 4 Kei Nishikori, who opened his hardcourt season with the title in Washington at the weekend. World No. 1 Novak Djokovic is the top seed.

"One of the weeks I'm more happy with the whole season. Playing worse or playing better, I have to remain very stable. I was not able to do it very often this season," Nadal said in Montreal.

"That should be the way that I have to play, because one of the stronger points in my career is obviously the shots, but also the mental part. This year, I've felt the mental part was more up and down than usual. I'm working well and I'm hoping that week (in Hamburg) will help me here."

Despite losing his top three ranking in the world, Nadal was sure he would not lose his ability to smile. "Normally I don't lose the smile. I do not have one reason to lose the smile, even if I lose 100 tennis matches in the future," Nadal said.

"In general, I feel very lucky about my life, how it goes. I have the people that I love around me. I have the general health of myself. I enjoy playing golf. My live very close to the sea. I enjoy being near the sea. I enjoy scuba diving, swimming, fishing.

"When I'm at home, I do the normal things a 29-year-old guy does. I go out with friends, I visit family, cinema, golf... normal things. I enjoy life outside of tennis. Tennis has been a very important part of my life, for sure, but I always say the same: Tennis is not everything for me."

Nadal said retirement was not on his mind.

"I'm pretty sure that I'm not going to be playing tennis until I'm 39. But that's part of how my career and life goes. I have to keep going and for the moment, it's difficult to think of retirement.

"A lot of people ask, when are you going to stop playing tennis? When that moment arrives, I will know.

When I wake up in the morning and I don't have motivation to go and practice, to improve something... that will be the end. Until that day arrives, I'm here and I'm enjoying it." (Agencies)