Osaka drawing inspiration from family at United Cup
Four-time Grand Slam champion Osaka, who won Australian Open titles in 2019 and 2021, said she was taking inspiration from her two-and-a-half-year-old daughter Shai as she began the new year.
"My daughter is an incentive, she's (always) in the back of my mind. There are a lot of incredible moms on the tour," the 28-year-old said in Perth on Thursday.
The 16th-ranked Osaka, who ended her 2025 season in mid-October with a leg injury, last faced Sakkari in 2021 with the Greek player, now ranked 52nd, dropping just four games in a resounding quarter-final win in Miami.
Osaka said her off-season had been a balancing act, but that she was feeling good.
"I was able to spend time with my daughter while I recovered from a long season, even if I didn't play the entire thing," said the former world number one.
"My form will hopefully be good in my matches. I feel in shape and excited for the upcoming season."
Osaka had originally entered the ASB Classic in Auckland to kick off her season heading into the Australian Open at Melbourne Park on January 18, but had a change of plan.
"I enjoy the team atmosphere," she said. "I've wanted to play the United Cup for a long time. You get to play the best in the world straight off the bat."
The 18-nation mixed-team event opens with group matches in Perth, followed by Sydney a day later.
Ties comprise one men's and one women's singles and a mixed doubles, with group winners in each city advancing to the quarter-finals along with the best runner-up.
More than $11 million in prize money is at stake alongside ATP and WTA ranking points.
Osaka said becoming a mother had changed her outlook on tennis, which used to dominate her life.
"I used to take the wins and losses so seriously, they defined me as a person. Now I take every day as a new opportunity to do better," she said.
"My biggest role is not as a player but as a mother to my daughter.
"The off-season was difficult," she added. "I had to try to be there for her but there were moments when I had to train, I hope I'm handling it well.
"I hope when she's older that she understands why I did what I did."
Japan are also grouped with a British team led by Emma Raducanu.