What we saw in the thrilling three-set quarterfinal encounter between Venus Williams and Kim Clijsters is that Venus didn’t quite have the mental or physical stamina and fitness to see an after-midnight match to a winning conclusion.

Win over Serena cost Venus
At the outset of the match, it almost seemed as if Williams was going to have a quick go of it. She was pumped up and leading 6-4, 4-2, not to mention serving for a 5-2 lead. But Clijsters, who just didn’t seem to be able to counter Williams for the initial part of the match, showed some impressively steely nerves to work her way to a dramatic 4-6, 7-5, 6-1 quarterfinal victory.

I think what told the tale was when Clijsters was able to rebound in the second set -- we saw her come alive at that point and Venus start to deflate. For Venus, she just seemed to tire quickly, and it was a fatigue that was both physical and mental.

From the mental aspect, I truly believe that Venus was worn out from the drama of playing her sister Serena in the fourth round last Sunday. I think all the hype about the sisters playing is emotionally draining for both of them each time they play.

It was particularly noticeable how tired Venus was in the third set when she went down two service breaks to 4-1 for Clijsters. She had difficulty serving effectively as her toss lowered and her power waned. You could also see how fatigued Venus was in her inability to move about the court as well as she did in the first two sets of match.

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I was somewhat surprised at the way Williams lost her energy since it was actually cool for the first time during the tournament -– so heat and humidity was not an excuse that could be offered.

Looking at the bigger picture
I’m sure Venus will find it a bit difficult to think back about how she sizzled early, but then visibly fizzled to watch Clijsters win 11 of the last 13 games in the match. But I do hope that Venus doesn’t get too down on herself from this loss. Certainly she is a champion and champions internalize and take losses hard. But Venus has to also look at the year she’s had and understand how important her victory at Wimbledon was in her career.

Many of us questioned whether Venus would have the ability to rebound and once again become a major factor in the game. Well, she proved that she had the desire to win big again, and she put in all the work required to do so.

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Now she has five Grand Slam trophies and while this U.S. Open won’t be added to her trophy shelf, if she keeps playing as she has been, there’s likely to be other major rewards in the future.

I was glad to hear Venus say after the match that she is feeling good about where her career is at and that she’s happy that she was able to bring in one Grand Slam title this year. Without a doubt, it’s important for Venus to take a positive attitude from here to build on this year.