* Nadal wins first hardcourt match in nearly a year
* Shows no sign of discomfort with left knee (Adds further quotes, detail)
INDIAN WELLS, California, March 9 (Reuters) - With the tennis world watching closely, Rafa Nadal made a successful return to Indian Wells with a 7-6 6-2 victory over Ryan Harrison in the second round of the BNP Paribas Open on Saturday.
Though initially looking a little rusty, the Spanish left-hander showed no visible sign of discomfort after being sidelined for seven months last year by a left knee injury before sealing a commanding win in just over an hour and a half.
Playing his first match on a hardcourt surface in 346 days, Nadal edged a close first set 7-3 in the tiebreak, then broke Harrison's serve in the third and fifth games of the second to take firm control.
The Spanish world number five, who had his left knee taped up through the match, served out to book his place in the third round, ending Harrison's brave challenge with an overhead smash to spark loud roars from the crowd.
"It was a good victory for me today against a good opponent," Nadal, who clinched the Indian Wells title in 2007 and 2009, told reporters. "I am satisfied to be in the next round. That's the most important thing.
"Two weeks ago, I didn't really know if I would be here playing. I am happy to be here. I am happy to be in the third round."
Asked how he felt after the match, Nadal replied: "I am fine. My physical performance needs to improve. My movements need to improve. Matches like this help for me sure, no?
"Today, more than any result, any victory is important because that gives me the chance to play another day. I need to compete. That's the only way to play well in a short period of time."
Nadal, who has enjoyed a successful tournament run on clay in recent weeks, was given an electrifying welcome by a vocal crowd when he first walked out on to the showpiece Stadium Court at the Indian Wells Tennis Garden.
He made a confident start, racing into a 4-1 lead before his 73rd-ranked opponent broke back in the seventh game to take the opening set into a tiebreak.
Nadal, who had occasionally blasted his ground strokes long as he tried to find his range, stormed 5-1 ahead in the tiebreak before wrapping up the set in 54 minutes after he struck a deep forehand which forced an error by Harrison.
The Spaniard did not look back, breaking Harrison in the third game of the second set with a stunning crosscourt pass and also in the fifth with a dipping forehand service return which the American could not retrieve.
While Nadal did not attempt to slide in his customary manner as he moved from side to side in some of the longer baseline rallies, he did not appear to be in any discomfort on the surface expected to trouble him most following his knee injury.
"After seven months, I'm not going to take crazy risks," said the 26-year-old, who won his 11th grand slam title at the French Open last June.
"But I am here. When I am playing a tournament, if you know me, my mentality is to try my best in every moment.
"For my first tournament on (a) hard (surface) and with the conditions, I don't expect a big result but just to be here, to practise with the other players, compete like I did tonight and have another chance tomorrow."
The Spaniard, who 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, will next face Leonardo Mayer of Argentina.
Mayer brushed aside Russian Mikhail Youzhny 6-2 6-3 earlier in the day. (Reporting by Mark Lamport-Stokes; Editing by Patrick Johnston)