American tennis star Amanda Anisimova has made a shock change to her appearance at the Australian Open after opting to become a brunette.

Anisimova, 23, returned to tennis last year after taking an eight-month break from the sport to focus on her mental health amid frequent messages from trolls about her appearance.

Yet almost exactly 12 months after ending her hiatus, the former French Open semi-finalist has completed a stunning transformation after ditching her usual blonde hair for a dark brunette look.

Amanda uploaded a photo of herself showing off her new hair color on Instagram and wrote: ‘Why not’.

At the age of just 21, Anisimova briefly walked away from tennis after being brutally mocked by trolls on social media for having ‘giant boobs’.

Before announcing she was taking a break from the sport the New Jersey-born star, whose parents emigrated to the US from Russia, shared a screenshot of one user’s cruel jibe to her on Instagram.

‘The most unathletic body ever! Narrow shoulders and giant boobs,’ the message read.

She initially replied to the comment with ‘Thank you’ and a kissing emoji before sharing it to her story and writing: ‘Idk what to think? lol.’

Anisimova then added: ‘The amount of people who comment on my body every day on social media… will never understand what the hyper fixation is about.’

After losing in the first round of the Madrid Open in 2023, Anisimova revealed she would be stepping back from the sport while struggling with her mental health.

‘Hey guys. I thought I’d make a post explaining what’s been going on and my plans,’ she explained. ‘I’ve really been struggling with my mental health and burnout since the summer of 2022.

‘It’s become unbearable being at tennis tournaments. At this point my priority is my mental well-being and taking a break for some time. I’ve worked as hard as I could to push through it. I will miss being out there, and I appreciate all the continuous support.’

Since making her return in January 2024, Anisimova – currently ranked 36th in the world – has played at the US Open, French Open and the Australian Open twice, making it to the fourth round of the latter competition last year.

She is set to face Argentina’s María Lourdes Carle in her first-round tie on Tuesday.