Matildas forward Larissa Crummer has led Brann to their their second win in as many Women's Champions League matches, scoring the only goal in a victory over Slavia Prague.
The former Newcastle Jets and Brisbane Roar attacker headed home from close range in the 21st minute on Wednesday night (Thursday AEDT) in Norway.
The 27-year-old Queenslander had a chance to ice the game on 87 minutes but missed the target.
"It was quite tough with the wet conditions and the heavy field," Crummer said.
"It was a bit of a grind the last 30 minutes. But we worked hard as a team and that's what got us through."
Also in Group B, fellow Australian Ellie Carpenter's Lyon recorded a 2-0 win over St Poelten.
Carpenter and Crummer both played full games in their respective home games.
The French club, and eight-time winners, will host Brann on Matchday Three in three weeks time.
"We've got a lot of confidence. We might not have gotten off to the best start but we really applied ourselves in the second half," Carpenter said.
"With match after match, we've got to stay confident, stick to our gameplan, and keep our heads up."
Elsewhere, defending champions Barcelona defeated Eintracht Frankfurt 3-1 in Germany and Benfica were 1-0 winners over Rosengaard in Group A action.
Four more matches take place on Friday (AEDT) with Sam Kerr's Chelsea hosting Sarah Hunter's Paris FC, while Hayley Raso's Real Madrid travel to Sweden to face Aivi Luik's Hacken, also in Group D.
In Group C action, Clare Hunt's Paris Saint-Germain are at home to Bayern Munich and Roma welcome Ajax Amsterdam to the Italian capital.
