Eventually it became clear even to Federer that he was going to lose Wednesday night — that for the first time since 2003, he was he not going to participate in the U.S. Open semifinals.
"So many moments, I thought, 'Man, it's just not happening for me,'" the 17-time Grand Slam champion said. "It was just a very disappointing match for me."
Able to muster his best shotmaking only occasionally, the top-seeded Federer was stunned by No. 6 Berdych of the Czech Republic 7-6 (1), 6-4, 3-6, 6-3 in the quarterfinals at Flushing Meadows.
It was Berdych's fourth victory in his last seven meetings against Federer, including in the 2010 Wimbledon quarterfinals en route to a runner-up finish to Rafael Nadal at the All England Club.
How did Berdych explain his success against Federer? After all, Berdych never had been past the fourth round at the U.S. Open and was coming off first-round losses at Wimbledon and the London Olympics.
"It's probably the way that, with my game, I'm able to make him some trouble," said Berdych, who will play Olympic champion Andy Murray in Saturday's semifinals. "There is something in my game that he doesn't like, and it makes him a bit struggle, I would say, and maybe bring him out of his comfort zone."
Perfect analysis, Tomas.
Although Federer did not agree.
"The power is not really the issue here," Federer said. "I don't think that was a problem for me. The problem was elsewhere."
Perhaps. Still, the 6-foot-5 Berdych did keep pounding serves and groundstrokes right where he wanted them, pushing Federer this way and that and finishing with a total of 14 aces, 30 winners and only 21 unforced errors.
Federer, meanwhile, made 24 of his 40 unforced errors off the forehand side.
He hadn't competed since Saturday, and he looked rather rusty, particularly for the first two sets against Berdych. The man Federer was supposed to play in the fourth round Monday, Mardy Fish, withdrew because of a health scare.
But Federer essentially dismissed that as a possible explanation for his rather un-Federer-like performance, shrugging his shoulders when asked if that was important.
"I don't know. I hope not. I have been there before. Once I had 6 1/2 days off and I ended up winning Wimbledon," he said. "I don't think this was the issue tonight."
In dark sneakers bearing a tiny gold trophy with a black "5'' etched on it — representing his title count at the U.S. Open — Federer made things more interesting by winning the third set, but he couldn't maintain that momentum in the fourth.
He won the championship in New York every year from 2004 through 2008, but his 40-match winning streak at the hard-court major tournament ended with a loss to Juan Martin del Potro in the 2009 final. Federer then was beaten by Novak Djokovic in the semifinals in 2010 and 2011.
This year, Federer took another step backward, bothered by another big hitter.
Berdych absolutely controlled the opening-set tiebreaker, capping it with a 128 mph ace.
And then, quick as can be, he broke to begin the second set, first smacking a superb forehand winner down the line on a full sprint, then watching Federer miss two wild forehands on consecutive points.
Berdych broke again in the third and led 3-1 there before Federer began to find his form. Berdych also hurt himself, showing signs of nerves by double-faulting twice while getting broken to 3-all.
That was part of a stretch in which Federer took four games in a row and 19 of 24 points to take the third set. He ended it with a perfect drop shot, and all of a sudden, the possibility of a ninth career comeback from a two-set deficit seemed possible.
Berdych, after all, had blown such a lead to Federer before, in the fourth round of the 2009 Australian Open.
Not this time, though.
"I wasn't celebrating too much," Federer would say later.
At 2-2 in the fourth, Federer conjured up a terrific cross-court backhand passing winner that left Berdych skidding and stumbling as he tried to change directions while moving toward the net. Berdych dropped his racket as he fell, scraping his fingers along the blue court.
After taking several seconds to compose himself — and to press a cold water bottle against his hand — Berdych lost the next point, too, to fall behind love-30, then claimed the next four points to hold for a 3-2 lead.
And three games later, Berdych smacked a cross-court forehand winner to break Federer and make it 5-3. All Berdych had left to do was hold serve once, and he did it, delivering a 124 mph ace to get to match point, and a 124 mph service winner to convert it.
"When you leave it a little bit on Roger's game, and he starts to go for it, it could be a really big problem," Berdych said. "So I was just trying to get it back, trying to get my rhythm back again, and to stay as close as possible. And finally it was the right moment, right tactics."
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