Top seed Roger Federer [Images] maintained his stranglehold over Croatia's Ivan Ljubicic with a 7-6, 7-6, 7-6 win to lift his second straight Nasdaq-100 Open title on Sunday.

Victory in two hours, 56 minutes for the Swiss world number one earned him an American tournament double for the second year in a row after back-to-back wins in Indian Wells and Miami [Images].

"I'm extremely happy," Federer told reporters. "To win back-to-back like this is unbelievable. I never thought I'd do it again. It really feels great."

The Swiss, who has now won 28 of his last 30 finals, is unbeaten in Masters Series tournaments since he lost to Richard Gasquet in the Monte Carlo quarter-finals last April.

He has now beaten Ljubicic in their last seven ATP meetings and took his 2006 win-loss record to 28-1 -- a run that includes four titles.

"It was tough today, he made me work very hard," said Federer, who will soon turn his concentration to the clay season and a run at the Roland Garros title in Paris.

"He could have pushed me further if he'd played better on big points in the tiebreaks," added the Swiss.

"But he was going for big serves with great variation. He made me work but I expected that -- three tiebreaks is the most extreme you can have."

BIT ROUGH

Four of Federer's meetings with Ljubicic have come in finals with the Swiss now 10-3 against Croatia's Davis Cup captain.

"I played well but it's still a loss, it feels a bit rough," Ljubicic told reporters. "He never misses in tiebreaks and comes up with his best shots when it's important."

Favourite Federer had to overcome more than 20 unforced errors in a 59-minute opening set that ended when he fired down a sixth ace in the tiebreak.

The Swiss went up a break for 4-3 in the second set but Ljubicic broke straight back but after two hours he had a two-set lead after another tiebreak.

Federer then recovered from a break down in the third set before closing out the match in another tiebreak to claim his 10th career title at a Masters Series event including the last four in a row including Hamburg, Cincinnati and Indian Wells.

"You wish the match would have finished different," the Croat said of Federer's net cord return that clinched victory. "But this is tennis, that's just another way to win a point.

"But you cannot say he won because he was lucky. At that moment it was bad luck for me."

The Swiss, who had never won three tiebreaks in a match and admitted he had closed it out on "a very lucky match point", was playing his 11th straight Masters Series final since June, 2005.

Federer triumphed in eight of the previous 10 finals, losing only to David Nalbandian in Shanghai at the Masters Cup and to Rafael Nadal [Images] in Dubai last month.

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