NEW YORK (AP) As Roger Federer so correctly noted, the exact score of a tiebreaker is not all that important. All that matters is who wins it.
Still, it was noteworthy that Federer became the first player to shut out John Isner in a tiebreaker - and later added a rare service break of the big-serving, 6-foot-10 American, too - while winning their fourth-round U.S. Open match 7-6 (0), 7-6 (6), 7-5 on Monday night.
According to the ATP, Isner had never lost by a 7-0 score in 428 previous official tour-level tiebreakers.
''You've got to get a little lucky,'' Federer said in an on-court interview, ''but 7-love is a very good score, obviously, against John. As long as you win the `breaker, it doesn't matter what the score is.''
Isner called the way that tiebreaker went ''surprising.''
''That was a lot on me,'' Isner said, covering his face with his left hand. ''He had a lot to do with that, as well.''
Federer also broke to close out the match, ending the 13th-seeded Isner's streak of 110 consecutive service holds at Flushing Meadows over the last two years.
''The break clearly was nice, but I kind of felt it was coming,'' said Federer, who went 0 for 9 on break points until converted his 10th. ''He was maybe not having as much energy anymore.''
Federer saved all five break points he faced, while finishing with an impressive ratio of 55 winners to only 16 unforced errors.
The second-seeded Federer, who has won five of his 17 Grand Slam titles in New York, has not dropped a set on the way to a quarterfinal against No. 12 Richard Gasquet of France.
Gasquet got past No. 6 Tomas Berdych 2-6, 6-3, 6-4, 6-1.
With losses by Isner and Donald Young on Monday, this is the 16th consecutive Grand Slam tournament without an American man in the quarterfinals. Isner and Andy Roddick made it that far at the 2011 U.S. Open.
Isner did have his chances against Federer. Six times, Isner was two points away from grabbing the second set.
But Federer was at his best down the stretch in that tiebreaker, too, after trailing 5-3. Federer won one point by returning a 140 mph serve before smacking a forehand passing winner. On another, he produced a forehand return winner off a 128 mph serve to earn a set point. And he capped the set by flicking a down-the-line backhand winner.
''I really would have liked my chances against some other players out there. But he was too good,'' Isner said. ''That's what I was up against. There's nothing you can do about that.''
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