Meanwhile, Naomi Osaka retired from the final of the Auckland Classic with an abdominal injury.

The four-time Grand Slam winner, who was playing in her first WTA final for three years after taking a 15-month break and giving birth to her first child midway through 2023, took the opening set 6-4 against Denmark's Clara Tauson.

But the 27-year-old called for the physio at the changeover and stood and performed a series of stretches during a medical timeout.

After consulting with the trainer she shook the hand of Tauson, who picked up a third career title and her first since 2021.

In a statement, the WTA said Osaka retired "due to an abdominal injury".

"I just want to thank everyone for welcoming me to such a beautiful city and I had a lot of fun playing here and I'm really sorry about how it ended," she said.

"I hope you did enjoy the tennis that we did play and I'm just really grateful to be here."