Naomi Osaka will undergo a scan on the injury that forced her to pull out of the Auckland Classic final but remains optimistic about playing at the Australian Open, the former world No. 1 said on Monday.

Osaka, the 2019 and 2021 champion at Melbourne Park, was reduced to tears on Sunday when an abdominal injury forced her to quit while leading Clara Tauson 6-4 in her first WTA final in almost three years.

"I'm having an MRI today to assess," the 27-year-old said in a brief statement.

"I don't feel that it's too serious and I still feel very optimistic about AO."

Osaka, who returned to the tour a year ago after a long maternity break, had shown glimpses of the form that won her four Grand Slam titles during her run to the final in Auckland.

She returned to the Top 50 in the world rankings on Monday.

Reigning Wimbledon champion Barbora Krejcikova, however, said Sunday that she was pulling out of first Grand Slam of the season due to a back injury.

"Unfortunately, my back injury, which troubled me at the end of last season, is still not fully healed," the world No. 10 said on X.

"It's really disappointing because I love playing in Melbourne and have such great memories from reaching the quarterfinals last year." "I'm working hard to get back to full health, and I can't wait to see you on the court soon," Krejcikova added.

The Australian Open begins on Sunday.