Serena Williams of USA had to pull out of her Fed Cup match against Belgian Kirsten Flipkens because of minor inflammation in her right knee.
Serena's injury appeared after her Saturday's match against Caroline Maes, and her captain decided to replace her as a precaution.
Williams' team said that this injury is not related to her groin injury which, two weeks ago, forced her to leave the tournament in Charleston.
However, Serena's young replacement, Vania King added another point to the U.S. by defeating the Belgian player in three sets 4-6, 6-4, 7-5. This victory puts the U.S. into the Fed Cup semifinals where they will face Russia. (sources: Tennis Magazine, Fed Cup official website)