Kei Nishikori has warned his fans a breakthrough grand slam victory may still take some time.

The Japanese star, who became the first Asian man to reach a grand slam final by reaching the decider of the 2014 US Open, began his Australian summer of tennis in strong form at the Brisbane International.

The world No.5 fell at the semi-final stage at Pat Rafter Arena for the third straight year when he was outlasted by Canada’s Milos Raonic in a 151-minute epic on Saturday.

The 6-7 (4-7) 7-6 (7-4) 7-6 (7-4) loss to the world No.8 Raonic meant Nishikori bowed out of the tournament despite his serve not being broken.

Nishikori’s best performance at the Australian Open was a quarter-final in 2012 and the 25-year-old says just because he’s shown he can reach grand slam finals doesn’t mean he’s on the verge of a flood of titles.

“Winning might take some time, you know?,” he said.

“You need some luck too when you play … hopefully (it) comes one day I win a grand slam.

“That’s my dream, so hopefully I can do it in a few years.”

He may be taking a cautious approach when it comes to grand slam prospects but Nishikori was feeling good after his Brisbane tournament, especially after nearly defeating Raonic despite the big-hitting Canadian sending down a whopping 34 aces in their match.

He’ll head to Victoria to compete in next week’s Kooyong Classic hoping to build on his impressive form in Brisbane.

“I think it was a good start to the year for me,” he said.

“I have more confidence and am playing better tennis and physically I’m much more fit.”