Serena Williams photo The world’s No. 1 ranked player, Serena Williams pulled out of the 2009 Open GDF Suez tournament played in Paris, France. She was scheduled to play Elena Dementieva in the semifinal match.

Williams cited a knee injury as the reason for her withdrawal. Williams was quoted in Argwus tennis blog, “At the end of the match (against Emilie Loit) I felt pain and this morning it was bad. My left knee has already often been injured and here it’s the right, that’s the good news… I really think it’s just a question of a few days of rest.”

Sources report that she immediately left for a bigger tournament in Dubai and will have only three days rest. Some question her real reason for withdrawing, as though she didn’t really take the tournament seriously.

It will be interesting to see how Williams plays in Dubai. That might tell us whether or not the knee injury was real.