Tommy Haas is a German professional tennis player who has been ranked as high as world number two in the ATP rankings. He has won 15 singles titles and has been a finalist in three Grand Slam tournaments. He is known for his powerful serve and aggressive baseline play. He has also been successful in doubles, winning four titles. Haas has been a member of the German Davis Cup team since 1999 and has helped them to reach the finals in 2007 and 2008.