Juan Mart??n del Potro is an Argentine professional tennis player.In 2008, he became the first player in ATP history to win his first four career titles in as many tournaments. He also completed the second-longest winning streak in 2008, and the second longest by a teenager in the Open Era, behind Rafael Nadalƒ??with his winning sequence spanning 23 matches over five tournaments. Del Potro captured his first Grand Slam title at the 2009 US Open, defeating Nadal in the semifinal and Roger Federer in the finalƒ??the first man to defeat them both in the same Grand Slam tournament. Del Potro also won the bronze medal in men’s singles at the London Olympics in 2012.