The sporting press, cynical by nature, is always looking for The Moment.
That critical-mass instance when a star athlete's career crests and begins to descend. Three years ago, in the crucible of March Madness in Miami, Roger Federer appeared to cross that threshold, smashing his racket in an eerie echo of his tempestuous junior days.
This spring, Miami may have again produced that same, sad window to a career suddenly, startlingly on the decline. Strapping Rafael Nadal, who still looks like he could play strong safety in the NFL, withdrew from his semifinal match against Andy Murray.
"Today I have a really bad [left] knee and the last couple of days were tough for me," a clearly dejected Nadal explained in a news conference. "I am not ready to compete.
"I am very sorry for the fans."
And nearly all the fans -- those who truly love the sport -- were sorry that day for Rafa. In retrospect, it looks like that flaring of tendonitis (or something more ominous) was The Moment.
We learned Wednesday that Nadal will miss the U.S. Open later this month.
In a statement, in which the sentiment and tone is growing all too familiar, Nadal said, "I am very sad to announce that I am still not ready to play and have to withdraw from this year's U.S. Open in NYC. I am sorry since I always found great crowds and great support, but I have to continue with my recuperation and preparation to be ready to play in the right conditions.
"I'll miss you all this year at the Open!"
And the would-be No. 3 seed will be missed, too, perhaps even a little by Federer, Novak Djokovic and Murray. For tennis is infinitely more compelling when Nadal is healthy.
Frankly, it does not look good. There are rumors swirling in Spain that Rafa needs surgery. Coach Uncle Toni, always cautious and tempered in his approach, is said to be holding out for more treatments. It would have been two months between matches if Nadal had played the U.S. Open.
"It's dramatic and it's disappointing," said ESPN analyst Brad Gilbert. "But people shouldn't be pushing the panic button on Rafa. Knowing him, he'd probably like to be out there -- maybe he could have actually played. But he has a great team around him, and I'm sure they'll do what's best for him.
"The thing is, we think it's fixable. Rafa has had a few scopes, but never serious ACL-type surgery. I think this means he's done for the season and they'll try and get him right for 2013."
It's important to remember Nadal has rallied before -- even earlier this year. He rebounded from that physical meltdown in Miami with typical dash and grit. He won titles at Monte Carlo, Barcelona, Rome and Roland Garros -- ending an 0-for-7 streak against world No. 1 Djokovic with three resounding finals victories. But his seventh French Open title came at a terrible price.
It may have looked easy, like old times, but we now know Nadal's 26-year-old knees barely made it through his retro run in Paris. He later lost in the second round of Wimbledon to a player ranked No. 100 in the world. How bad were those knees this time? Although Nadal was the defending Olympic singles champion and chosen to be the flag bearer for Spain in the opening ceremonies, he withdrew from London 2012, calling it "one of the saddest days of my career." That was stunning enough, but then Nadal pulled out of the ATP World Tour Masters 1000 event in Toronto. And then Cincinnati. And now New York.
Darren Cahill, who has been involved with coaching a number of today's top players, including reigning Wimbledon champion Federer and Olympic gold medalist Murray, is as plugged in as anyone in the game.
Yet when asked about Rafa's status a few weeks ago, he responded, "I don't know. Why don't you tell me about Rafa?"
Later, he added, "Rafa has always taken playing for his country in Davis Cup extremely seriously -- to miss the Olympics must have been a huge decision for him. You can't deny it: He's been struggling with this for a number of years.
"The good news is that it's not new territory for him. He has managed this condition and he's risen above it."
The knees first became a serious issue in 2009, when Rafa skipped Queen's and Wimbledon. But because he was also dealing with the separation of his parents, it was impossible to know how much of his decision was based on his deteriorating physical condition -- or his damaged emotional state. It remained the only major he has missed in a span of 26.
There is an irony to the situation Nadal finds himself in. The same relentless attitude, the extreme physicality of his game that brings opponents to their knees has put his at risk.
To this day, Nadal moves better on clay than any other player. That he wins more matches on the surface where the rallies are longest is a self-fulfilling prophesy of the inevitable damage he inflicts on himself. And don't discount the stress on the joints of his left side. Nadal's average forehand has been measured at 600 revolutions per minute more than other players. That heavier ball may take a toll on his shoulder, elbow and wrist as time goes on.
When Nadal won in Paris it was his 11th Grand Slam singles title, tying him with Rod Laver and Bjorn Borg for fourth on the all-time list. After Federer and Borg, Nadal is the third fastest to 11 majors but, in light of his recent struggles, can he possibly maintain that pace?
There was a time when it seemed possible that Rafa -- like Tiger Woods bearing down on Jack Nicklaus -- might catch Federer in the race for major championships. But when Federer triumphed at Wimbledon, he pushed his total to 17. Nadal may well win another French Open or two or three, which means he could conceivably equal Pete Sampras' total of 14. But can Nadal come back to win another title or two on the punishing hard courts in Melbourne or New York? Before you answer, consider that he hasn't won a hard-court title since Tokyo in the fall of 2010. Based on what we saw this year, can he put together back-to-back Euro Slams and also win the title at Wimbledon, as he did in 2008 and 2010?
In fairness, it should be noted that after his troubles in 2009, Nadal returned to play in nearly "perfect conditions" in 2010 -- the best year of his career -- and 2011. That said, because of its surface and back-loaded schedule the U.S. Open is the most physically demanding of the Grand Slams.
This may have been a factor in his thinking. Remember his uncharacteristic complaints at last year's U.S. Open, when rain condensed the men's schedule into the second week?
"So," Gilbert said, "we're not going to see the big four out there. Instead of two great guys on each side of the draw, we'll have two on one side and one on the other. That means that No. 5 and No. 6 are going to feel better about their chances; they're going to get some better looks at the basket.
"You're always concerned when it comes to knees, but Rafa's only 26. You just hope he can get it fixed and get back to the game."