Novak Djokovic of Serbia (L) and Rafael Nadal of Spain pose with their first and second-place trophies respectively after their Madrid Open final tennis match, May 8, 2011. [Photo/Agencies]

* Serb grinds out 32nd win of the year, sixth title

* Nadal beaten on clay for the first time in 38 matches

MADRID - A relentless Novak Djokovic dethroned clay king Rafa Nadal on the Spaniard's home soil and maintained his extraordinary season when he stunned the world number one 7-5 6-4 to win the Madrid Masters title on Sunday.

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The Serbian second seed ground down the local favourite and defending champion during a succession of ferocious rallies to record his 32nd consecutive win of a defeat-free 2011, the best season start since John McEnroe's 42-match streak in 1984.

The defeat marked Nadal's first reverse on his beloved clay in 38 matches since he fell to Robin Soderling in the fourth round of the 2009 French Open and denied him a third title on the red dirt in under a month after he won back-to-back at the Monte Carlo Masters and Barcelona Open in April.

Djokovic, who had never beaten Nadal on clay in nine previous attempts, now has six titles this year, including the Australian Open and the Masters in Indian Wells and Miami, where he beat Nadal in both finals.

The question now is whether the 23-year-old can carry the momentum into the French Open later this month, the only one of the four grand slams played on clay where champion Nadal has claimed five of the past six crowns.

"First of all to Rafa bad luck today," Djokovic said after collecting his winners trophy and 590,000 euros ($824,200) first prize. "It's always a big challenge to play you, you are a great champion. Hopefully we can have many more matches."

Rafael Nadal of Spain reacts during the Madrid Open final tennis match against Novak Djokovic of Serbia, in Madrid, May 8, 2011. [Photo/Agencies]

After picking up his runners-up trophy and cheque for 275,000 euros, Nadal praised Djokovic's achievements and said he needed to analyse what went wrong in the match and move on.

"He is playing at a great level this year and you just have to accept that," the 24-year-old said.

"I'll have to look at what I did wrong and go forward with the right attitude and look for solutions and how to improve.

"Evidently, I wasn't playing at my best level on clay but I didn't play such a bad match either. Just that against a very good Djokovic it wasn't enough today."