NEW YORK -- This one was supposed to be a layup.
Although his ATP World Tour ranking has fallen to No. 7, Roger Federer was playing at the US Open, where he has been a champion five times. He was facing Tommy Robredo, a Spaniard of substance, in a fourth-round match that would deliver the winner to a probable quarterfinal against Rafael Nadal.
How could Federer, who had won all 10 of their previous meetings -- and 24 of 27 sets -- possibly lose?
It will be written that some saw this one coming.
This one came out of nowhere, as Robredo -- only nine months younger than Federer -- beat Federer for the first time, 7-6 (3), 6-3, 6-4.
"I kind of feel like I beat myself," Federer said, "without taking any credit away from Tommy. Clearly he was making sure he was making many balls. It was up to me to make the difference and I couldn't. I kind of self destructed, which is very disappointing, especially on a quicker court.
"I just couldn't do it. It was a frustrating performance today."
After a 4½-hour rain delay, the match was moved from Arthur Ashe Stadium to the more intimate Louis Armstrong venue and, in retrospect, it seemed to be a foreshadowing. Federer had won seven straight matches on that court, going back to his US Open debut in 2000, when he lost to Juan Carlos Ferrero in the fourth round. The last time Federer lost in straight sets here? In 2002, to Max Mirnyi.
And the last time he failed to reach at least the quarterfinals in back-to-back majors? More than a decade ago, at the 2003 Australian and French Opens.
"Well, that's amazing," said Robredo, perhaps understating what had just happened. "I beat the best guy of all time, in this stadium, in a place he loves to play. It's unbelievable."
Federer fashioned 16 break points on Robredo's serviceable serve -- and converted only two. Robredo was bigger in the big moments, collecting four of seven.
Federer, one of the most cerebral and judicious players in tennis history, consistently forced the issue by coming to net behind flawed approach shots. And, when he was forced out of position on the baseline, tried to compensate by taking some uncharacteristically wild swings.
In the third set, the Armstrong crowd was giving Federer sympathy claps and cheers, usually reserved for far lesser players. At the same time, in the media room, there were a number of groans and sad sighs when the man they have seen win almost every time out went down so badly.
And so, there will be no 32nd meeting between Federer and Nadal, but merely an intra-squad match, assuming Nadal wins, between two Spanish Davis Cup team members.
In his great novel, "The Sun Also Rises," Ernest Hemingway captured precisely what has happened to the 17-time Grand Slam champion.
"How did you go bankrupt?" asks a character.
"Two ways," comes the reply. "Gradually, then suddenly."
Federer won 16 of 27 Grand Slam singles titles in an astonishing period from 2003-10. In three different seasons (2004, 2006, 2007), he won three of four majors.
But since winning the 2010 Australian Open, at the age of 29, Federer has no longer been automatic at the Slams. In the subsequent Grand Slams, Federer has managed to win only one of 15. That one was a wonderful back-to-the-future victory a year ago at Wimbledon. Federer fans have wondered if their champion had one more major in him, like Pete Sampras at the 2002 US Open.
History will probably show that the 2012 Wimbledon title was that last glorious last-gasp moment at the top.
Here is how Federer has fared at the five Grand Slams since: 2012 US Open (lost to Tomas Berdych in the quarterfinals), 2013 Australian Open (lost to Andy Murray in the semifinals), 2013 French Open (lost to Jo-Wilfried Tsonga in the quarterfinals), 2013 Wimbledon (lost to Sergiy Stakhovsky in the second round).
Taken by itself, that horrible defeat at Wimbledon might not be the death-knell for Federer, but in conjunction with this performance, the question begs itself: Can the 32-year-old Federer ever again be a truly viable contender for a Grand Slam singles title?
There have been signs that Federer himself is feeling the tremors.
Was he lacking in confidence?
"Yeah, probably," Federer allowed. "Confidence does all these things. It takes care of all the things you don't usually think about, you know. But I just think it's been a difficult last three months.
"Maybe my consistency is just not quite there yet. Maybe on a daily basis, set-by-set or point-by-point basis, maybe that's something that has been difficult for me. So maybe that was one of the reasons I lost today."
He started playing with a midsized racket after Wimbledon, eight square inches larger than his trusted Wilson Pro Staff 90. That experiment didn't go well and he arrived in New York with his trusty axe that delivered him so many championships.
Federer, even today, can make the game of tennis seem incredibly simple -- and beautiful. He sailed through his first three matches here, not dropping a set. In his third-round victory over Adrian Mannarino, the Swiss player dropped only five games.
And then he ran into Robredo, the No. 19 seed. He was broken in the very first game, but rallied to force a tiebreaker. Federer was serving at 4-3, when Robredo sent a wicked backhand volley behind his approach. A forehand passing shot gave him an insurmountable lead.
The second and third sets followed a similar pattern. Robredo managed to win those points when his serve was threatened; Federer didn't.
"I had been struggling with Roger 10 times," a delighted Robredo said in his on-court interview. "Today before the match, I thought, 'What are we going to do?' Do your best, and play all the points. In the end, I did the break points and he didn't.
"Even if I was really close to dying, I will still fight. I'm really happy."
Throughout his career, Federer has generally displayed impeccable timing. On this evening, he was off. Did that make his performance look worse than it actually was?
"Maybe," Federer said. "Look, then again, it's always been a fine line, especially in the beginning of my career when I didn't have the results to back me up. People thought, 'Did he even try? Does he care much?'
"Now, with the results, I know you don't believe that so much. That's the good thing. The story of my life: When I lose, people are shell-shocked to see me play this way. If I win, it's the best thing. Yeah, I can see that.
"But there's no doubt about it, I'm trying hard out there trying to make it work. Sometimes it just doesn't happen."