Blackjack!

In so many instances the number twenty-one holds great importance. Whether it's the passage into adulthood, a guaranteed win at the card table, or the number of firings in a royal salute, reaching twenty-one in any effort has a special meaning.

And last night Kim Clijsters attained that exalted number at the U.S. Open.

Her win over Vera Zvonareva in the women's final was a little shocking in its one-sidedness, but less so when you consider that Flushing Meadows has become Clijsters' home Slam. She came here in 2005 after missing the previous year due to wrist injuries, but stormed to the championship match by taking out two-time titleist Venus Williams in the quarters and top-seeded Maria Sharapova in the semis. For the trophy she took out veteran Mary Pierce in straight sets, dropping only four games to win her first Major title.

The next year, though, continued problems with her wrist and a couple other injuries forced her to pull out of the Open and she soon after announced her retirement from the sport. Though her personal life stayed busy -- she got married, had a daughter -- we didn't see her on the tennis court again until 2009, when she gave a solid showing in Cincinnati and Toronto before really making a statement in New York.

Only three tournaments into her comeback, she wasn't seeded or even ranked, so understandably she faced a draw full of recently emerged champions -- Marion Bartoli took her to three sets in just the second round, Venus gave her an oddly-scored win in the fourth, while her defending champion sister Serena infamously foot-faulted her own way out of the tournament. In the finals against first-time Major finalist Caroline Wozniacki, Kim battled through a tough first set, but ultimately claimed her second U.S. Open trophy in quite emotional fashion.

By the time she returned to Flushing Meadows this year, Clijsters had climbed her way back to #3 in the world and earned herself the second seed. She was playing even better tennis than she had in '09, winning the title in Cincinnati -- the tournament at which she had begun her return the previous year, and sailed through her early round matches without dropping a set. She was tested in the second week by Sam Stosur and, yet again, Venus Williams, but eventually reached the finals with a chance to defend her title for the first time.

Admittedly, I gave her opponent Vera Zvonareva a slight edge in the match. The Wimbledon finalist had defeated Kim on her run at the All England Club and followed that up with another solid victory over the Belgian in Montreal. She hadn't lost a set in her first six rounds in New York and was able to stay steady against top-seeded Wozniacki in the semis to prevent a repeat of last year's championship match.

But Clijsters was nearly unstoppable Saturday night. Though she'd been streaky in some previous matches, falling for example to an 0-4 deficit in the second set after bagelling Greta Arn to open her first match, she was clean throughout this one. She ran off to a quick lead in the first set before breaking Vera again close it out, and kept right on rolling in the second. Keeping her cool amid small meltdowns by the Russian, Kim needed just an hour to dispatch Vera and claimed her third championship on Arthur Ashe's stadium.

That's twenty-one straight match wins in New York. Twenty-one victories over solid opponents, some favored over her either on paper or in reality. Twenty-one contenders whose hopes for a trophy of their own have been dashed at the hands of Kim Clijsters.

The way she plays here, it's really no wonder her challengers have no choice but to fold their hands.