The Serbian recovered from dropping his opening service game to win the first set 6-3.

He then secured four games in a row to take the second by the same margin for the set and broke for a fifth time to win the match in less than 90 minutes in a tournament that a ATP World Tour Masters 1000 event.

The 28-year-old now moves level with United States legend Andre Agassi in having claimed six Miami victories and also becomes the first man to win the Indian Wells and Miami Open Masters Series double three years in a row.

"It's quite amazing," said Djokovic.

"I'm very thrilled about it and hopefully I can make many more records.

"I thought he [Nishikori] started very well, breaking my serve in the first game and coming up with some aggressive play.

"I needed to answer right back, which I did in the following game - that helped me mentally."

Djokovic, who also moves ahead of Rafael Nadal with a record 28 Masters tournament wins in his career, is now targeting victories this year at the two tournaments that have eluded him so far: the French Open and the Olympic singles title.

"It's tough to find his weakness, honestly," said Nishikori of his opponent.

"The biggest thing is he has great defence and it's tough to open up the space."

The match followed Belarus' Victoria Azarenka's victory over Russia's Svetlana Kuznetsova yesterday in the women's competition, 6-3, 6-2.