Over his legendary tennis career, it has always been foolish to write off 24-time Grand Slam title winner Novak Djokovic.

Novak Djokovic was beaten 7-6 (6), 6-3 by big-serving Reilly Opelka in the Brisbane International quarterfinals on Friday.

Novak Djokovic was playing his first tournament of the year in preparation for the Australian Open which he has won 10 times.