Naomi Osaka's first tournament since becoming a mother ended in a 3-6, 7-6, 6-4 second-round loss on Tuesday night to three-time champion Karolina Pliskova at the Brisbane International.

Osaka, who has won the Australian Open and the U.S. Open singles titles twice, won her first match at the elite level since late 2022 on Monday in straight sets against Tamara Korpatsch.

After that win, she said the birth in July of her daughter, Shai, and the changes to her mindset since becoming a mother had given her a better perspective on tennis.

A second-round encounter featuring two former No. 1-ranked players was a step up in tempo and a better indication of how Osaka´s preparations are going for the Australian Open starting Jan. 14 in Melbourne.

'The week is definitely shorter than I wanted it to be,' Osaka said in a news conference. 'Overall, I think it was a great match and I had a lot of fun.

'I've trained so hard since giving birth, I need to enjoy these moments.'

Osaka won the first set but Pliskova recovered and fired 16 aces and hit 50 winners, saving 10 of the 12 breakpoint chances she faced and making amends for her 11 double-faults.

'I saw the stats after and my break points could have been better,' Osaka said.

'But I think other than that we both played really well ... so hopefully she says the same thing!'

A former finalist at Wimbledon and the U.S. Open now ranked 39th, the 31-year-old Pliskova was playing for the first time since September after a left wrist injury curtailed her 2023 season.

'A lot of things to improve, but a good start,' to the season, said Pliskova, who had her left wrist and hand taped for the opening match of the day on Pat Rafter Arena.

Top seed and defending Australian Open champion Aryna Sabalenka had a 6-3, 6-0 win over Lucia Bronzetti of Italy in the following match.

Second-seeded Elena Rybakina, the 2022 Wimbledon champion, was scheduled to meet Olivia Gadecki in a night match.

Osaka's next match will be an exhibition in Melbourne on Rod Laver Arena, the main court for the Australian Open, next week.