Answer
The answer is David Nalbandian. Nalbandian is a former Argentine professional tennis player who achieved a career-high singles ranking of world No. 3 in March 2006. He is best known for his powerful forehand and his success on clay courts. Nalbandian defeated Federer in the third round of the 2003 Wimbledon Championships and in the quarterfinals of the 2005 French Open.