Former world number one Naomi Osaka said Thursday that she was looking at "a bigger picture" and not just results since returning to tennis late last year after giving birth.

The four-time major winner has not gone beyond the quarter-finals in six tournaments since her 15-month maternity break, with her latest match a third-round defeat to France's Caroline Garcia at the Miami Open last month.

Osaka, whose world ranking has risen from 831 to 193 since her return, will play for Japan in their Billie Jean King Cup qualifier against Kazakhstan in Tokyo starting Friday.

The 26-year-old said she was encouraged by her form and had "played really good players the entire comeback".

"It's really tough to look at it results-wise," she said. "But I have to look at it in a bigger picture and try to expand on my game and expand on the knowledge that I'm constantly learning as a player."

Osaka described her second-round win over Ukraine's Elina Svitolina in Miami as "one of the better matches in my career, just in terms of execution".

Osaka is appearing at the Billie Jean King Cup for the first time since 2020, after being asked to play by team captain Ai Sugiyama.

"She's just always felt very kind and genuine and I always really wanted to try, just to be better in team atmospheres as well," said Osaka.

It will be Osaka's first appearance in Tokyo since she withdrew from the Pan Pacific Open in September 2022 before her second-round match.

The tie will take place at Ariake Coliseum, where Osaka reached the third round of the Olympics in 2021. She has said she wants to represent Japan at the Paris Games this year.

Kazakhstan will be without world number four Elena Rybakina, who lost to American Danielle Collins in the Miami Open final.

Osaka and Nao Hibino are Japan's singles representatives and will take on Kazakhstan's Yulia Putintseva and Anna Dalinina.

The winners will advance to November's finals in Spain.

Osaka said she wanted to show the Tokyo fans "something really exciting" to demonstrate how she has matured as a player.

"When I was younger, I tried a lot to hit a lot of crazy shots -- now I'm a little bit more strategic," she said.

"I hope that it's fun for everyone to watch, but I'm not going to do anything crazy."