Novak Djokovic and Andy Murray have known each other for a quarter of a century. They played from the age of 12, meeting 36 times as professionals, including 10 Grand Slam matches.

Murray, who retired in August, jokingly blames Djokovic as the main reason he never captured an Australian Open title.

It will be all business when Andy Murray coaches Novak Djokovic at the Australian Open. While the partnership between two of the biggest rivals in recent men’s tennis history has awakened feelings of shock,