MELBOURNE, Australia (AP) — Defending Australian Open champion Naomi Osaka withdrew from her semifinal match Saturday at a WTA tournament with an abdominal injury, allowing her opponent Veronika Kudermetova to advance to the final on a walkover.

“I had a lot of fun playing here in Melbourne. Unfortunately I have an abdominal injury which I need to rest and prepare for the Australian Open,” Osaka said in a statement issued by Tennis Australia.

“Sad to withdraw due to injury from my match today, my body got a shock from playing back to back intense matches after the break I took,” Osaka added later on Twitter. “I’ll try to rest up and I’ll see you soon!”

The Australian Open begins Jan. 17.

Kudermetova on Sunday will face second-seeded Simona Halep, who beat Zheng Qinwen 6-3, 6-2 in the other semifinal Saturday in the Summer Set 1 event.

At the Adelaide International, Wimbledon champion and top-ranked Ash Barty beat former French Open winner Iga Swiatek 6-2, 6-4. In Sunday’s final, Barty will play Elena Rybakina, who beat Misaki Doi 6-4, 6-3.

American Amanda Anisimova advanced to her first final since 2019 with a 6-2, 6-0 win over Daria Kasatkina in the Summer Set 2 event at Rod Laver Arena. Next, Anisimova will play Aliaksandra Sasnovich of Belarus, who beat Ann Li 7-6 (4), 2-6, 6-3.

In the semifinals of an ATP tournament at Melbourne Park, Rafael Nadal beat Finland’s Emil Ruusuvuori 6-4, 7-5. Nadal will face American Maxime Cressy in Sunday’s final. Cressy beat Grigor Dimitrov 7-5, 7-6 (9).

The Adelaide and Melbourne tournaments are among six tune-up events being staged in Australia this week ahead of the season-opening major at Melbourne Park.