Here's a short story:

(CNN) -- Samantha Stosur stopped Caroline Wozniacki from clinching the year-end women's No. 1 tennis ranking with a shock 6-4 6-3 victory at the WTA Championships in Qatar on Wednesday night. 

The Australian romped to her second straight victory in the Maroon Group, following her revenge win over French Open champion Francesca Schiavone on Tuesday. 

The Roland Garros runner-up's kick serve was a potent weapon against Wozniacki, with the triumph giving the 26-year-old every chance of reaching the semifinals ahead of her final group match against Russia's Elena Dementieva on Thursday. 

It was her second victory over a top-ranked player this year, having beaten Serena Williams on the way to reaching the final in Paris. 

The fifth seed fired 26 winners to Wozniacki's 14, and could afford to serve two double-faults in the deciding game before the Dane returned a backhand long on her first match-point. 

Wozniacki, who thrashed seventh seed Dementieva on Tuesday, will next take on Italy's Schiavone on Thursday. 

Kim Clijsters, who won the $4.5 million season-ending event in 2002 and 2003, earlier triumphed in her opening White Group match 6-2 6-3 against fellow former No. 1 Jelena Jankovic despite serving 10 double-faults. 

The Belgian, returning to action after having a mole cut off her foot, broke Jankovic to love in the first game of the match and then again in the seventh. 

The three-time U.S. Open champion was less impressive in the second set but had enough to see off the Serbian, who is struggling with illness in the oppressive heat in Doha.  (End of story)

Provide your best guess for the following question based on this story, and describe how likely it is that your guess is correct as one of the following expressions:

Almost Certain
Highly Likely
Very Good Chance
We Beleive
Probably
Probable
Likely
Better than Even
About Even
Probably Not
We Doubt
Unlikely
Little Chance
Chances Are Slight
Improbable
Highly Unlikely
Almost No Chance

Give ONLY the guess and your confidence, no other words or explanation. For example:

Guess: <most likely guess, as short as possible; not a complete sentence, just the guess!>
Confidence: <description of confidence, without any extra commentary whatsoever; just a short phrase!>

Here are a few examples of questions and answers:

Question: What kind of win did Stosur get against Schiavone?
Guess: Revenge win
Confidence: <appropriate level of confidence in this guess>

Question: True or False: Stosur played against Wozniacki on Friday morning.
Guess: False
Confidence: <appropriate level of confidence in this guess>

Question: When did they play each other?
Guess: Wednesday night
Confidence: <appropriate level of confidence in this guess>

Now answer the following question in the same format.

Question: How old is Stosur?

26-year-old