( CNN ) -- King of Clay Rafael Nadal began his defense of his Monte Carlo Masters title Wednesday with a routine 6-4 , 6-3 victory against the Finnish player Jarkko Nieminen . Nadal , whose incredible form on clay has seen him go unbeaten at the tournament since 2003 , showed little discomfort in dispatching Nieminen despite suffering persistent injury problems with his left knee . The Spaniard had pulled out of the Sony Ericsson Open semifinal against Andy Murray to receive treatment and also missed several tournaments after the Australian Open . `` I need practice , and today was a good practice , '' Nadal told AFP . `` Tomorrow ( is ) going to be another tough match against a player who is dangerous . '' That `` tough match '' will be against Kazakhstan 's Mikhail Kukushkin . If Nadal wins it will be his 39th straight win in the tournament and put him on course for a record eighth title . `` It was the first match on clay after a long time , and the first match after 15 days without touching a racquet , '' said Nadal . `` The important thing was that I won in straight sets . Tomorrow I have another chance to keep improving , and that 's what I 'm going to try . '' But Nadal is n't the favorite to win . Top seed and world number one Novak Djokovic looked impressive after beating Italian Andreas Seppi 6-1 , 6-4 . `` I was really focused first set and played it well against a tough , quality opponent who plays good on clay , '' explained Djokovic . `` For the first official match since [ the French Open at ] Roland Garros last year , it was satisfying . '' Djokovic will play the Ukrainian Alexandr Dolgopolov in the second round in the hope he can finally break Nadal 's clay court stranglehold in Monte Carlo and beyond . `` We 've played already here finals in 2009 , good match , but Nadal is the ultimate challenge on clay , '' Djokovic said on Monday . `` He 's the king of clay . He 's the best tennis player ever to play on this surface and one of the best tennis players ever , so that says enough . `` Obviously , knowing in 2011 I won Rome and Madrid and winning against Rafa in finals back-to-back gives me a lot of confidence for coming into the clay court season now . ''
Rafael Nadal beats Jarkko Nieminen in first round of Monte Carlo Masters . Defending champions Nadal aiming for a record eighth title . Tops seed Novak Djokovic beat Alexandr Dolgopolov in first round . Djokovic aiming to break Nadal 's clay court stranglehold .