(Corrects to "knee injury" from "ankle injury" in 2nd par)
* Nadal beats Federer in straight sets
* Will meet Berdych in semi-finals
INDIAN WELLS, California, March 14 Rafa Nadal produced vintage form against an out-of-sorts Roger Federer, crushing the Swiss 6-4 6-2 in their heavily anticipated quarter-final at the BNP Paribas on Thursday.
The Spanish left-hander, competing in his first hardcourt event since his return from seven months on the sidelines with a knee injury, outplayed his long-time rival with a sharp display at the Indian Wells Tennis Garden.
Nadal broke the defending champion once in the first set and three times in the second to wrap up victory in one hour 24 minutes in front of a packed house on the Stadium Court.
The Spanish world number five improved his record against Federer to 19-10 and will next face sixth-seeded Czech Tomas Berdych, who swept past big-serving South African Kevin Anderson 6-4 6-4 earlier in the day.
"After seven months away, I am very happy to be in the semi-finals here," a beaming Nadal said courtside after taking advantage of a slew of backhand errors by his opponent, who has been struggling with a back niggle throughout the tournament.
"I don't think Roger felt 100 percent tonight. Always it is a very, very special match against Roger, the best player in history. I feel like it is a classic match whenever we play."
With a near-capacity crowd eagerly watching, the opening set went with serve until the seventh game when Nadal, who had looked surprisingly sharp, broke Federer with a stunning crosscourt backhand pass to lead 4-3.
Federer saved two set points on his serve in a protracted ninth game but the Spaniard served out in the 10th, taking the set when a backhand service return by the Swiss sailed wide.
Moving much more fluently than his opponent and finding his range with searing crosscourt forehands, Nadal broke Federer in the first game of the second set when the Swiss, lunging to his right, was unable to return a dipping crosscourt shot.
Federer also failed to hold serve in the third, saving one break point before the Spaniard unleashed a crunching forehand pass to lead 3-0.
The Swiss immediately rebounded by breaking Nadal's serve for the first time in the match in the next game when his opponent hit a backhand long, then held for 2-3.
However, with Federer continuing to make unforced errors, the Spaniard again broke his opponent in the seventh game before serving out for the match in the eighth.
Asked how much of a problem his troublesome back had been against Nadal, Federer replied: "Same as against Stan (Stanislas Wawrinka, his opponent in the previous round).
"I am happy to be out there and able to compete. It's always an issue and doesn't work against a guy like Rafa. But I don't want to undermine his performance here." (Reporting by Mark Lamport-Stokes; Editing by John O'Brien)
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