Cameron Smith on fire early at the Queensland PGA

Crediting a diet of crumpets and coffee, Cameron Smith has opened his Australian travelling roadshow on fire to be right in the mix after the first round of the Queensland PGA Championship in Brisbane.

Australia's one-time world No.2 reeled off four birdies in a five-hole stretch on the back nine en route to a five-under-par 67 at Nudgee Golf Club on Thursday.

Smith is outright third, trailing only joint leaders Phoenix Campbell, the defending champion, and his exciting young understudy Billy Dowling by one stroke after round one.

The US-based 2022 British Open champion is back home for a four-tournament summer stint in Australia, keen for competition after plying his trade these days on the relatively leisurely but lucrative LIV Golf Tour.

Smith had to set his alarm for 4am to make his 6.45am tee time and, after starting from the 10th tee, took a while to shake off the rust.

He bogeyed his first hole before collecting his first birdie of the day on the par-4 16th, then edging in to red figures with another on the next.

Smith clicked into top gear with four further birdies on the second, fourth, fifth and a chip-in "bonus" at the sixth before finishing with three straight pars.

He conceded nerves contributed to an errant tee shot on the first before his breakfast for champion's kicked in.

"Some crumpets with honey, not a nutritional breakfast, then a coffee and I was on my way," the laidback Queenslander said.

"A really solid round."

Clearly the class act in the field, the 30-year-old is a hot favourite to win the $250,000 PGA Tour of Australasia event.

But he reserved special praise for co-leader Dowling, a former Cam Smith scholarship holder who he's spent plenty of time mentoring, including this week while staying together.

"Yeah, he's a good kid. I love Billy," Smith said.

"He was one of the shyest kids ever on one of those trips and it's good to see him playing really good golf.

"It does make me a little proud and I just hope he can figure out what he wants to do and kind of go on his own way."

Smith will also contest the NSW Open in two weeks at Murray Downs near the Victorian border before shooting for a fourth Australian PGA Championship crown at Royal Queensland from November 21-24.

He will round out a busy summer down under at the Australian Open co-hosted by the Victoria and Kingston Heath golf clubs in Melbourne from November 28 to December 1.