Grigor Dimitrov made a strong start to the new ATP season with a comfortable 6-3 6-4 victory over Yoshihito Nishioka in round one of the Brisbane International.

The Bulgarian was champion at the 2017 event, which was the catalyst for a brilliant season that yielded a run to the Australian Open last four and ATP Finals glory.

He will look to reclaim that form after an underwhelming 2018 and the sixth seed made a great start in Brisbane saving six of seven break points in an ultimately comfortable win.

"I felt I was actually hitting the ball quite all right for our first match of the year," he said.

"There [were] a few things that I would like to maybe improve in the next match, but overall I think it's off to a positive start."

Brisbane-born John Millman is next up for Dimitrov after he won a deciding set 6-0 against Tennys Sandgren with the first two having been won on tie-breaks.

Milos Raonic, champion in 2016, raced past Aljaz Bedene 6-0 6-3 in just 47 minutes to book a round-two date with qualifier Miomir Kecmanovic, who saw off Leonardo Mayer 6-3 6-1.

Yasutaka Uchiyama also progressed from round one, the Japanese defeating fellow qualifier Ugo Humbert 6-4 7-6 (8-6).