World number one Novak Djokovic defeated Japan's Kei Nishikori 6-3, 7-5 Sunday to win the Toronto hardcourt tournament and claim his 66th career singles title.

The Serb top seed collected his seventh trophy of the season as he duplicated his win over Asia's top player three months ago in the Miami final.

Djokovic improved to 10-2 in the series as he handed Nishikori a defeat in just 81 minutes.

Djokovic now leads the Masters 1000 winner list by two over Rafael Nadal (28).

"I had to realize my level," Djokovic said.

"I was not feeling that comfortable at the start of the week. But I made progress and gained in confidence at the right time."

Nishikori was run down in the first hour of play before staking a brief claim on the contest.

The Japanese player recovered from a break down in the second set, leveling at 3-all and taking his first lead over Djokovic 4-3 in the next game.

But Djokovic re-established himself with a break for 6-5, taking victory a game later on his third match point with a service winner that flew off Nishikori's racket.

"It was a shame to lose the final but it was still a great week for me," Nishikori said.

"I'm going to the Olympics next week and I hope to carry this momentum with me."

Djokovic credited his serve for seeing him through.

"I'm glad I had that weapon today. Kei is one of the best returners on the circuit and a very fast guy -- I had to serve well to win. "

Djokovic finished with 13 winners as he improved to 51-4 this season.

He now heads to the Rio Olympics to battle for gold: "It's gonna be a great honor and pleasure to be part of such a renowned and recognized sporting event. The Olympics are really special, I will give my best to fight for a medal."