Rybakina leads Kazakhstan to BJK Cup victory over Australia
The world number 10 battled past Kim Birrell 6-3, 7-6 (7/4) at Pat Rafter Arena in Brisbane, rallying from 3-1 down in the first set and 5-1 behind in the second.
It gave Kazakhstan an unsurmountable 2-0 lead after world number 23 Yulia Putintseva outclassed teenager Maya Joint 6-2, 6-1 in just 74 minutes in the opening rubber.
"Such a difficult match and super happy to bring the win for the team, and Yulia did a great job in her match," said Rybakina, who has an 8-1 win singles record at the BJK Cup -- previously known as the Fed Cup.
"I played pretty well in the first set, but it was difficult and I was just trying to fight in the second set when I was down."
Putintseva added: "It was definitely a good game for me and I love playing in Brisbane. I think today was just one of those days when everything was working."
All ties are best-of-three -- two singles and a doubles.
Kazakhstan meet Colombia at the same venue on Friday and will progress to the finals at Shenzhen in China this year if they win. Australia face Colombia on Saturday.
The BJK Cup qualifiers feature six groups of three nations as the finals transition from a 12-team tournament to an eight-team event, mirroring the men's Davis Cup format.
Later Thursday the Czech Republic take on Brazil, Poland face Switzerland and Germany play the Netherlands with each group winner joining hosts China and defending champions Italy at the finals.
Teams finishing second and third in each group will move to November play-offs, alongside the best-performing countries from the 2025 regional Group I events.
Those group play-off winners will book their place in the 2026 qualifiers.