Alexander Zverev enhances reputation as Grand Slam challenger with ATP Finals win vs Daniil Medvedev
![Alexander Zverev enhances reputation as Grand Slam challenger with ATP Finals win vs Daniil Medvedev](https://i.dailymail.co.uk/1s/2021/11/21/19/50786639-0-image-a-88_1637524602865.jpg)
Even if he does end going to the Australian Open in January, Novak Djokovic was served a reminder last night that a tenth title in Melbourne is far from assured.