The Austrian leads by three from a group of seven players including tournament host Paul Lawrie, who opened with a three under par round of 68 on a benign day on the Balgownie Links.
Brier started quickly with four birdies in his first six holes to make the turn on four-under-par, before adding two further birdies coming home to take a commanding lead after 18 holes.
“It was easy to play today really,” he said. “There was hardly any wind and no rain so the course was really there to play for.
"I started well; I holed a couple of good putts on the first six holes and that really got me into the round.
"From then on I really played solid, hit a lot of greens and then holed the odd short one and a couple of longer putts so I felt really good.”
He added: “It’s important to start quickly because you don’t get a lot of chances here. You really have to hit it close and sometimes downwind it’s not easy because you have to get it close to the hole.
"It was my second bogey-free round in a row after Paris last week so I’m happy, I’m on a roll.
“I found something after that round in Paris where I really played terrible. I’ve really got my swing going now and I only hit one or two bad shots out there today, the rest I was happy with.”
Defending champion Lawrie shares second place with six others, including countryman Gary Orr, English quartet Peter Baker, Jim Payne, DJ Russell and Gary Wolstenholme, alongside Canadian David Morland IV.
Scot Euan McIntosh, Switzerland’s André Bossert, France’s Marc Farry, South African James Kingston and Denmark’s Steen Tinning are a shot further back in a tie for ninth place on two under par.
The Alliance Pro-Am is being played alongside the Scottish Senior Open and it is currently being led Englishman JP Lilley, who recorded 36 Stableford points on day one. He is two points clear of fellow Englishmen Richard Anderson and Feisal Nahaboo.