2012–15: Early stages Birrell competed in her first professional event at the Bendigo Tennis Centre in October 2012 at the age of 14. She gained her first professional ranking point a year later with a straight sets win over Elizabeth James after receiving a wildcard into the main draw of a tournament held in her home state of Queensland. She finished 2013 with a professional singles ranking of 847. where they lost in the first round to second seeds
Lisa Raymond and
Zhang Shuai. In November 2014, Birrell was given wildcards to the two
Bendigo International tournaments. In her debut at a $50k event, she defeated world No. 351,
Veronika Kapshay, in straight sets. In January 2015, Birrell was awarded a qualifying wildcard into the
Hobart International, but lost to
Vitalia Diatchenko in straight sets. She was then given a wildcard entry for the
Australian Open qualifying, where she fell to
Kateryna Bondarenko in three sets. Birrell also made her major main-draw debut at the event, after getting one of seven team wildcards in
women's doubles, alongside
Priscilla Hon, but lost in the first round to the fifth seeds,
Raquel Kops-Jones and
Abigail Spears. In March 2015, Birrell qualified for and made the first
ITF Circuit final of her career in Mildura, but lost to compatriot
Alison Bai in straight sets.
2016: Major & WTA Tour singles debuts, first WTA doubles final Birrell was awarded a wildcard into the qualifying rounds of the
Brisbane International, but lost to
Samantha Crawford. She made her
WTA Tour debut after being awarded a wildcard into the main-draw at the
Hobart International. She won in straight sets against world No. 57,
Danka Kovinić, before losing to
Dominika Cibulková in the second round. At the same tournament, she partnered
Jarmila Wolfe in the doubles where they made the final, but were defeated by
Han Xinyun and
Christina McHale. Birrell was awarded a wildcard into the
Australian Open but she lost in the first round to ninth seed
Karolína Plíšková. In February, Birrell made her
Fed Cup debut for
Australia against
Slovakia at the age of 17. She lost to Dominika Cibulková in straight sets. Shortly afterwards, she suffered a right elbow injury, sidelining her for the rest of the year.
2017–18: First ITF Circuit singles title Birrell and
Priscilla Hon were given a wildcard entry into the doubles at the
2017 Australian Open, losing in the first round to
Sam Stosur and Zhang Shuai. At the end of September 2017, she reached the final at the Penrith International, losing to
Olivia Rogowska. The following week in Brisbane, Birrell won her first ITF singles title by defeating
Asia Muhammad in three sets. Birrell won her second career ITF singles title at the
2018 Darwin Tennis International.
2019–20: Australian Open third round, first top-10 win, elbow injury and hiatus Birrell started 2019 with a wildcard entry into the
Brisbane International, where she claimed her first top 10 win over
Daria Kasatkina, before losing to
Lesia Tsurenko in the second round. At the
Australian Open, Birrell defeated
Paula Badosa in round one, earning her first Grand Slam main-draw win, before overcoming the 29th seed
Donna Vekić in the second round. She lost her third round match against three time major champion and second seed,
Angelique Kerber, in straight sets. In February, she played for Australia against the
United States in the first round of the
2019 Fed Cup World Group, losing to
Madison Keys, although Australia won the tie. Birrell lost in the first round of qualifying at
Wimbledon, which proved to be her last competitive match for over a year due to an elbow injury.
2021–22: Second hiatus and comeback Birrell played her first competitive match in 19 months at the
2021 Yarra Valley Classic where she lost in round one to
Mona Barthel. She was given a wildcard into the
2021Australian Open, where she lost in the first round to
Rebecca Marino. In February 2021, she made the third round of the
Phillip Island Trophy, at which point she lost to fourth seed
Petra Martić. It would be her final tournament for the year. In January 2022, she played her first professional match in 11 months, at the
Melbourne Summer Set 1, where she defeated
Martina Trevisan before losing to
Lesley Pattinama Kerkhove in the final qualifying round. Birrell then made the final round of the
2022 Australian Open qualifying.
2023: WTA Tour singles QF & doubles final, top 100, Australian No. 1 At the
Australian Open, she received a wildcard into the main draw, after the withdrawal of Venus Williams, and defeated 31st seed
Kaia Kanepi in a three set match lasting two hours and 32 minutes. It was her first Grand Slam tournament main-draw win in four years, the third top-30 career win and the fourth top-50 one. She reached a new career-high ranking of 136 on 13 February 2023, following her fourth ITF title. At the
Mérida Open, she reached her first WTA Tour quarterfinal as a qualifier, but lost to
Caty McNally, She achieved a new career-high of 116 on 27 February 2023. At the
Monterrey Open, she made her second WTA Tour doubles final, partnering
Fernanda Contreras Gómez, after receiving a wildcard. Birrell made her
WTA 1000 debut in
Indian Wells as a qualifier, losing to
Sorana Cîrstea in the first round. She also made her debut at the
French Open as a wildcard, but again fell at the first hurdle, this time to fellow wildcard entrant Leolia Jeanjean. In August, Birrell made her
US Open debut as a lucky loser, but was defeated in the opening round by
Jennifer Brady. After reaching the semifinals at the $100k event in Tokyo, she reached the top 100 on 18 September 2023.
2024: First WTA Tour final Birrell was awarded a wildcard into the
Australian Open in singles and doubles. In singles, she lost in the first round to
Jeļena Ostapenko. In doubles, she partnered
Olivia Gadecki, and together they scored a win over
Sabrina Santamaria and
Varvara Gracheva in straight sets. In the second round, the All-Aussie duo lost to eventual runners-up,
Lyudmyla Kichenok and Jeļena Ostapenko. At the
Nottingham Open, Birrell made her second career singles quarterfinal and her first on grass. She defeated
Emily Appleton for her first main-draw win of the 2024 season, and then overcame
Lucrezia Stefanini before losing to
Diane Parry. Birrell qualified for the main-draw of the
US Open, losing to 24th seed
Donna Vekić in the first round. She also qualified for the WTA 1000
China Open, making her debut at this tournament, but lost in the first round to lucky loser
Kamilla Rakhimova who she had defeated in the final qualifying round three days earlier. In October, Birrell qualified for the
Japan Women's Open and then defeated
Zheng Saisai, third seed
Elise Mertens, wildcard entrant
Sara Saito and
Aoi Ito to reach her first WTA Tour final where she lost in straight sets to fellow qualifier
Suzan Lamens.
2025: Australian Open mixed doubles final Birrell began her 2025 season at the
Brisbane International, where she received a wildcard entry and defeated qualifier
Priscilla Hon, second seed
Emma Navarro and
Anastasia Potapova to reach the quarterfinals, at which point her run was ended by
Anhelina Kalinina. Birrell qualified for the
Australian Open, but lost in the round to lucky loser
Eva Lys, after her scheduled opponent, 13th seed
Anna Kalinskaya, withdrew just minutes before their match was due to get underway. Partnering
John-Patrick Smith, she reached the
mixed doubles final, losing to
John Peers and
Olivia Gadecki. Entering as a wildcard at the
Singapore Open, Birrell defeated fifth seed
Polina Kudermetova and
Hailey Baptiste to make it through to the quarterfinals, where she lost to
Ann Li. Birrell won the
W75 Brisbane QTC International, defeating
Maddison Inglis in the final. As a result, she moved up 11 places in the WTA rankings to a career-high of world No. 75 on 10 February 2025. At the
ATX Open, she defeated fourth seed and defending champion
Yuan Yue in the first round, before losing to qualifier
Ena Shibahara. In March, Birrell qualified for the
Miami Open and defeated
Anastasia Potapova to reach the second round, where she lost to 23rd seed
Marta Kostyuk. Seeded seventh at the
Chennai Open in October, she recorded wins over
Nikola Bartůňková, wildcard entrant
Shrivalli Bhamidipaty and third seed
Donna Vekić to make it through to the semifinals, where she defeated
Joanna Garland, winning seven games in succession from 0–5 down in the third set and saving five match points in the process, to reach her second WTA Tour final. She lost the championship match to fourth seed
Janice Tjen in straight sets. Playing for Australia in the
BJK Cup play-offs in
Hobart, Birrell recorded wins over
Matilde Jorge and
Nauhany Vitória Leme da Silva as her team defeated
Portugal and
Brazil respectively to top their group and advance to the 2026 qualifying round.
2026: First WTA 500 semifinal Birrell reached her first WTA 500 semifinal at the
Adelaide International with a win over
Anastasia Potapova, a walkover against
Markéta Vondroušová and then defeating
Jaqueline Cristian, before her run was ended in the last four by eighth seed
Victoria Mboko. Having moved back into the world's top-100, she gained direct entry into the
Australian Open, but lost in the first round to fellow Australian, qualifier
Maddison Inglis, in three sets. At the same tournament, Birrell reached the quarterfinals in the
doubles partnering compatriot
Talia Gibson, defeating second seeds
Sara Errani and
Jasmine Paolini in the second round, then 16th seeds
Kristina Mladenovic and
Guo Hanyu in the third, before losing to
Ena Shibahara and
Vera Zvonareva in the last eight. In February, Birrell qualified for the
Dubai Tennis Championships and overcame
Tatjana Maria to make it through to the second round, at which point she lost to top seed
Elena Rybakina. The following week at the
ATX Open, she recorded wins over eighth seed
Petra Marčinko, qualifier
Caroline Dolehide and fellow Australian
Ajla Tomljanović to reach the semifinals, where she lost to fourth seed
Peyton Stearns. At the WTA 1000 tournament in
Indian Wells in March, Birrell defeated Tatjana Maria in a three-set match lasting almost three hours, before losing to 10th seed Victoria Mboko in the second round. In April, Birrell was part of the Australian squad for their
BJK Cup qualifier against
Great Britain in
Melbourne. She lost to
Harriet Dart in three sets. ==Performance timelines==