Proving that no good deed goes unpunished, a tale of great sportsmanship has instead turned into an investigation of gambling, match-fixing and tennis integrity.

Caroline Wozniacki, a 19-year-old Dane ranked sixth in the world, retired from the first-round match at the Luxembourg Open with a hamstring injury on Wednesday while leading Anne Kremer of Luxembourg 7-5, 5-0.

Wozniacki's father, Piotr, told his daughter at 3-0 in the second set to retire before winning because her injury would prevent her from playing in the next round. His comments, apparently spoken in his native Polish, were picked up by microphones and heard by viewers watching the match on the Internet ...

... The father's comments during the match led to a surge in online bets for Kremer to win.

Wozniacki did a tremendous thing for Kremer by allowing her to advance to the second round in front of her hometown fans. As she explained:

I could possibly have finished the match, but felt there was no way I could get ready for the second round on Thursday, so I chose the sporting way and let her go through. She's also [playing] at home.

For her selfless actions, Wozniacki has earned an investigation from the Tennis Integrity Unit. Because there were a number of bets made after her father's comments were picked up by the microphones, the WTA became concerned that there was something nefarious about Wozniacki's retirement.

The British gambling exchange site Betfair, which allows clients to make mid-match wagers, says it did not have any concerns about the match.

First of all, if Wozniacki was going to fix the match, there are dozens of more effective and less obvious ways to do it rather than retiring up 5-0 in the second set. That'd be like if Tim Donaghy tripped opposing players in the NBA games he bet on.

This also seems like the WTA's way of covering itself for having live microphones in coaching huddles. From the way this story was reported, the bets in question didn't go through until after Piotr Wozniacki's comments were aired live on the Internet. Why not just cut those mics?

In all likelihood, Caroline Wozniacki will be cleared of any wrongdoing, but it's still disappointing that she's set to be investigated for integrity after a gesture which showed how much of it she really has.

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