World No . 1 , and the United States is not a signatory to that treaty. Serbian stops Rafael Nadal 's bid to claim a ninth successive title . Djokovic avenges his final defeats by Nadal last year and in 2009 . The 25-year-old now has a 15-19 record against Nadal , whose last defeat on clay during the month of April was back in 2005 . Nadal 's last defeat in the principality was back in 2003 .
World No . 1 , and the United States is not a signatory to that treaty. Serbian stops Rafael Nadal 's bid to claim a ninth successive title . Djokovic avenges his final defeats by Nadal last year and in 2009 . Nadal 's last defeat in the principality was back in 2003 .