INDIAN WELLS, California (Reuters) - Buoyant after a successful tournament run on clay in recent weeks, Rafa Nadal knows he will face the toughest test of his injury comeback at the BNP Paribas Open starting on Thursday.
Following a shock second-round exit at Wimbledon last year, the Spanish left-hander was sidelined for seven months by a left knee injury and he now returns to the hard courts of Indian Wells, a surface where his all-action, fist-pumping game has always been most vulnerable.
"I am just here to try my best," world number five Nadal told reporters after practicing on one of the outside courts at the Indian Wells Tennis Garden. "We will see how the knee answers on hard.
"It seems that the results on clay were positive, especially because the knee was feeling better and better every week, especially the last week. Now I am going to try here on hard."
Nadal returned to the ATP circuit last month in South America where he competed in three relatively minor claycourt events, winning two of them after reaching all three finals.
He was especially pleased with his performance at the Mexican Open in Acapulco where he clinched the title after sweeping aside three-times defending champion David Ferrer 6-0 6-2 in little over an hour on Sunday.
"I played much, much, much better than what I thought and in Acapulco I played a fantastic tournament," Nadal smiled.
"And in the final at Acapulco, forget about if I was seven months away from tennis, I played much, much better than a lot of finals when I am competing at 100 percent. I played one of my best matches probably ever on clay in the final."
Asked how his troublesome knee was feeling as he prepared for the elite ATP Masters 1000 event at Indian Wells, Nadal replied: "I have good days and I have bad days during all the claycourt season.
"The important thing for me today is that most of the days I have changed the dynamic and I have much more good days than bad days. That's a positive thing.
"The only negative thing on clay when I have a bad day is your movements are easier than here (on a hardcourt surface)."
A left knee injury forced Nadal to pull out of the semi-finals in Miami last March - and began a chain of events that meant he would not play on hard courts again for a whole year.
Though he went on to win an 11th grand slam title at the French Open last June, his season came to an abrupt end two weeks later following a defeat to Czech journeyman Lukas Rosol.
Nadal ended up missing the U.S. Open and January's Australian Open but he said his biggest disappointment was having to skip the Olympic Games staged in London.
"That was the hardest," he added. "When I had to take the decision, I take it. I didn't have no choice. I couldn't move.
"That was a sad moment for me because these kinds of opportunities are not forever. Maybe it's only one time in life and I lost that opportunity. But I can always be positive, keep working and try to be in Rio in 2016."
Asked if he had ever considered quitting the sport during his seven months on the sidelines, Nadal replied: "I never thought about that.
"It was just a long time and sometimes it is hard when you practice every day in the gym, when you work a lot on the recovery and it's not an injury that you know exactly when you are going to come back.
"It's an injury that you look every day how the feeling improves or gets worse and sometimes it's frustration when you feel that every day you test yourself and feel that you are not improving. But I never felt about that (quitting)."
During his hiatus, Nadal said he enjoyed spending more time with his family and friends in Mallorca while also playing plenty of golf and going fishing, and could envision a life outside tennis.
"I can live without tennis," he added. "But when you cannot do what you want to do it is not easy. I am a competitor and I know this world is not forever, the tennis career.
"I really enjoy being a tennis player and I feel very lucky to have the chance to work in one of my hobbies. But life is a lot of things and sometimes much more important other things than the tennis."
(Reporting by Mark Lamport-Stokes; Editing by Pritha Sarkar and Frank Pingue)