By Larry Fine

NEW YORK (Reuters) - Twice defending champion Roger Federer faced two pressure-packed tiebreaks before seeing off a stubborn James Blake in the U.S. Open quarter-finals on Thursday.

Federer won the first set in a tiebreak and lost the third on another before winning 7-6 6-0 6-7 6-4 to reach his 10th successive grand slam semi-final -- matching Ivan Lendl's Open era record streak.

"I really thought that first set was unbelievable. From both sides," Federer said in a court-side interview after the two hour 47 minute match at Arthur Ashe Stadium.

"You make mistakes and he plays well and momentum shifts and all of a sudden it's a tough match."

Federer will meet seventh seed Nikolay Davydenko of Russia on Saturday for a place in the final. Davydenko advanced with a five-set victory over Germany's Tommy Haas earlier in the day.

Australian Open and Wimbledon winner Federer has won all seven previous matches against the Russian.

The other semi-final pits American ninth seed Andy Roddick, the 2003 champion, against unseeded Russian Mikhail Youzhny.

After winning the opening tiebreaker, spoiling three set points held by Blake, Federer looked poised to make the American his fifth successive straight sets victim, cruising to take the second set in only 22 minutes.

HARD-FOUGHT WIN

"That's just an old fashioned whuppin' in the second set," said Blake.

Blake, driven on by a boisterous support, battled back from a break down early in the third set but looked beaten when he lost serve to trail 5-3 and allowed Federer to serve for the match.

A sizzling forehand crosscourt winner in the next game got the break back and Blake sent the match to another tiebreak.

"To a certain extent I take pride in the way that I fought," said Blake, who had failed to win a set against Federer in his four previous meetings.

Federer saved four set points and held match point at 9-8 but Blake saved with a backhand winner down the line and took the next two points to force a fourth set.

The Swiss again looked set to sail to victory, going up by two breaks for a 5-1 lead before Blake hit back with a break of his own.

Federer finally dismissed Blake on his third match point of the game when the American dumped a backhand into the net.