PARIS - No era or dynasty ends on a specific day, although sometimes it may appear to. Who can forget the day the Berlin Wall came crashing down? Or that image of the last helicopter, taking off from the roof of the American embassy in Saigon with people hanging onto it? Yesterday, the day when Venus and Serena Williams both crashed out of Wimbledon within hours of each other, felt a little bit like one of those days.

It was a hectic, hot, humid day, a day when the air clung to your skin and the sky was right there above your brow, slightly portentious and somewhat oppressive. That, coupled with the fact that the sisters both lost in straight sets to women who didn't have a Grand Slam title between them (as opposed to Venus and Serena, who have a combined total of 20), probably helped advance that notion—one which Serena dealt with firmly if not with her trademark aggression when the question was put to her bluntly by a member of the press:

What would you say those who question whether this is the end of an era in terms of the Williams sisters dominance?

Serena replied, "I don't know. Like, I'm still here. I plan on doing better."

It was a good answer, not at all defensive. But it left me wondering, just what price is either sister willing to pay in order to add to her resume? For it's unlikely to get much easier from here on in, partly because Venus is over 30 and Serena rapidly approaching that landmark. And there have been signs this year, particularly in these last two major events, that the other women in the WTA are ready to move on. Ready to really challenge Venus and Serena in a way they would not have dared—in fact, did not dare—under less favorable circumstances a few years ago.

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My own reaction to the twin losses yesterday was a mild touch of melancholy. Maybe it was just that the results once again confirmed the relentless passage of time. Wasn't it just yesterday that Serena was tromping around in that ridiculous biker outfit she auditioned at the U.S. Open? What happened to willowy and lithe Venus, running down and whacking a ball so acrobatically that the WTA chose to make its logo out of the negative?

It didn't help that throughout the press room here at Wimbledon, reporters were scurrying around and firing out stats at each other—first time in 93 years that all eight quarterfinalists are European!  First time the sisters lost on the same day since—French Open, 2008! A reporter laid that trap for Venus during her presser, knowing the answer full well when he asked: When was the last time you and your sister both went out on the same day of a tournament?

"I don't keep the stats now," Venus frostily replied.

You can't remember a day yourself? 2008 French Open.

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"Thank you. Great to remember all these losses, right?"

But it was no use fighting that tide, it sweeps away all things. One thing that players absolutely don't understand when they're on top of the game is how swiftly their domain goes to pieces, how soon people forget, how frequently critics feel a measure of schadenfreude at the plight of all the most diplomatic and beloved of icons.

I wondered how others experienced that day; was it with their heads or hearts? Did they shrug and think, Well, the U.S. Open will be here soon. . . or brood, like I did, wondering if it something magical, frustrating, riveting and so easily taken for granted was coming to an end faster than I ever imagined it would. How did people feel?

"I was saddened," Bud Collins said. "I thought maybe both could move a little farther on. To many people, Wimbledon means the Williams sisters. But I don't get the feeling (that it's the end of an era). I would hate to see the end of this era because—I have to be jingoistic here—if it's the end, it's the end of the U.S. era, too."

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Chris Evert was talking with her fellow ESPN commentor Hannah Storm when I caught up with her. "It seemed anti-climatic to me," she said. "I wished the crowed supported Serena a little more, but I guess Bartoli won them over with her effort. I felt a little sadder for Venus. She went down so ... quietly. Serena, you know she'll be back. I believe she'll win a major again. But you have to wonder about Venus."

"I looked at their mother (Oracene)," Storm added. "I wondered, 'What must it be like to see both your children lose, back-to-back like that? I feel for the family, because they've always tended to support one another and when one of them was having troubles you could almost count on the other one to keep things going, to provide that lift. But this was like, 'Who do you turn to now?'"

Ken Solomon, CEO of Tennis Channel, said, "I've seen that 'end of an era' thing disappear really quickly. Two years ago, some people were saying Roger (Federer) would never do anything again. We've seen the Justine (Henins) and Kim (Clijsters') and Andre (Agassis) come back from much further down."

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Bethanie Mattek-Sands, who becomes the top ranked U.S. player (No. 31) on Monday, had a bad feeling about Venus' match when she saw that the older Williams sister was watching Serena collapse. "It was one of those matches where every television in the locker room is tuned to the match," Mattek-Sands told me. "It had to be tough for Venus to go out there after that, and in my opinion Pironkova played great. But for all we know, come the U.S. Open Series, they may dominate again."

I caught up with Todd Martin on the player's terrace, where he was talking with some old friends and former players. He said, "We've grown to expect that if not one then the other sister will succeed here, which is maybe why this feels a little strange. But then it's been an incredibly strange year for them. That inactivity clearly hurt. I guess it's tough for American tennis, but look—Mardy (Fish) did a great job today ..."

At that point, Tim Henman interjected, "It's a cycle. Look at us (the UK). We're at the bottom now, it just happens to be a real deep cycle."

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Everyone laughed.

"You used to dominate," Henman added, good-naturedly. "You've got no players. You're worse than we are."

"Don't you feel any sympathy for us?" I asked Henman.

"Not really," he replied. "You never knew how good you had it."

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