Women's world no. 1 Ashleigh Barty shocked tennis fans on Wednesday by announcing her retirement from the sport at the age of just 25. The Australian made the announcement through Instagram in an emotional video message with her close friend and former doubles partner Casey Dellacqua. The announcement comes just weeks after Barty became the first home-grown Australian Open champion in 44 years. In the video, Barty was also in tears towards the end and also said that she had been thinking about retiring since winning Wimbledon last year. Explaining why she chose Dellacqua to be present in her retirement video, Barty said, "I wasn't quite sure how I was going to do this. So many times in my professional and personal life, you have been there for me. I just couldn't think. There is no right way, there is no wrong way. It's just my way."