Sascha Zverev advances as Novak Djokovic retires from their match after losing the first set. ❤️‍🩹

Get well soon, @DjokerNole 

 📸Getty 
#djokovic #zverev #ausopen #atptour #tiebreaktennis
#djokovic #zverev #ausopen #atptour #tiebreaktennis