Wednesday 15 January 2020 10:18, UK
Angelique Kerber has suffered an injury scare just days before the Australian Open after being forced to withdraw from the Adelaide International with a back injury.
The world No 18 was 6-3 2-0 down to Dayana Yastremska when she retired from their round-of-16 match.
Kerber had earlier called for a medical timeout so a trainer could work on her lower back.
There was no immediate news as to whether the 31-year-old German's injury will prevent her from taking part in the Australian Open, which she won in 2016.
Kerber's withdrawal comes after she was knocked out of the Brisbane International at the first hurdle by Samantha Stosur last week.
The former world No 1 is a three-time Grand Slam winner, having also claimed the US Open in 2016 as well as winning Wimbledon in 2018.
