Boris Becker questions Novak Djokovic's desire and tactics in shock defeat

Djokovic was bidding to win a record seventh title at the Australian Open.

Novak Djokovic's former coach Boris Becker has criticised the Serbian for lacking fight and playing too defensively during his Australian Open defeat to Denis Istomin.

Becker and Djokovic split at the end of last year following a disappointing run of form for the 29-year-old, who failed to win Wimbledon, the Olympics or the US Open.