Tracy Austin

As impressive as Kim Clijsters' U.S. Open championship was, her ability to take two years off from competing and win a Grand Slam championship in just her third tournament back unearths flaws in women's tennis.

Never previously has there been a time in the sport where so many of the top women look fearful and tentative on the court.

Last year's U.S. Open runner-up, No. 5 seed Jelena Jankovic, and No. 4 Elena Dementieva, the 2008 Olympic gold medalist, were bounced in the second round. The third round marked the end of the U.S. Open campaigns for No. 1 Dinara Safina and No. 29 Maria Sharapova. By the fourth round, only seven of the top 15 women's seeds remained in the draw. In contrast, 13 of the 16 men in the fourth round were ranked in the top 15.

Their eliminations stood in marked contrast to the inspiring wins strung together by 17-year-old American Melanie Oudin. Even after dropping the first set multiple times against players against whom she was expected to lose, Oudin never conceded defeat or wavered in her self-confidence. Her fighting spirit, poise and underdog success captured the attention and imagination of even the most casual of tennis fans and made her one of the biggest stories to emerge from this year's U.S. Open.

Oudin's consistently positive mental attitude is something many of the top players lack. The absence of that tenacity is a major reason why no one player has emerged as the Tour's star and why the top-ranked women's player doesn't have a Grand Slam title to her credit.

It also explains why the mentally tough Clijsters was able to make such an immediate impact upon her return from retirement. While she was consistently among the Tour's best players from 2001 to her retirement in 2007, reaching a career high of No. 1 in 2003 and retiring while ranked fourth in the world, she faced a deeper pool of talent. In fact, Clijsters won just one Grand Slam title during that time.

Tennis today also features many talented players at the top of the rankings, but, excluding Venus and Serena, these players do not seem to have the mental toughness required to be truly dominant. The sport will continue to suffer until these competitors raise their games and prove themselves in clutch situations.

Putting aside these concerns, let's not lose sight of what Clijsters actually did accomplish. Her run to the championship was not paved with pushover opponents. In addition to beating No. 9 Caroline Wozniacki in straight sets in the final, the unseeded Belgian also had to knock off former Wimbledon runner-up No. 14 Marion Bartoli before defeating both No. 3 Venus Williams and No. 2 Serena Williams, a rare accomplishment in a single tournament.

While the end of Clijsters' semifinal battle against Serena was clouded in controversy with Williams losing match point due to a code of conduct violation, that doesn't change the fact that Clijsters outplayed her opponent virtually the entire match.

Recently it's been rare to find another player who can challenge Williams on the court. Clijsters didn't just challenge Williams, she pushed the American to the point of complete and total frustration. Clijsters managed to return shots that Williams was accustomed to admiring as winners, absorbing the power shots, extending rallies and forcing her opponent to go for too much.

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Williams took that frustration out on the lineswoman in an outburst that shocked those in attendance and the larger audience watching on TV. We've never seen a temper explosion like that from a female tennis player on such a big stage. A confluence of events combined to make the tirade one of the tournament's top stories: the use of profanity, the visibility provided by the TV broadcast, the importance of the match, the threatening manner in which it was delivered and that it involved one of the biggest women's tennis stars.

It's easier to excuse Williams' outburst than it is to explain her actions afterward. She reached her breaking point on court, an experience to which all of us can relate. But even after having time to collect herself, she still took no ownership of her actions in the post-match press conference. That's not the message she should be sending.

Williams eventually did make amends and apologized for her actions. It's nice to see that she finally realized her mistake and demonstrated how contrite she was. After winning the U.S. Open women's doubles title with sister Venus, Serena began the press conference by reiterating her apology.