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.

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,

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

Most notably, Andy Murray has been spotted coaching Novak Djokovic during his practice sessions. And the retired Brit is now set to return to the court himself after signing up to the pre-tournament 'A Night with Novak' event.

If Novak Djokovic Wins Australian Open, Andy Murray Would Be ‘Flooded With Coaching Requests,’ John McEnroe Says

Novak Djokovic's former rival-turned-coach Andy Murray does not want the Serbian to suppress his emotions on court and is even willing to be the target of any angry outbursts as long as the 24-times major winner gives his all at the Australian Open.

Andy Murray has signed up to play a pre-Australian Open event despite retiring just months ago. The five-time finalist at Melbourne Park is back Down Under in a new role this year, coaching Novak Djokovic. But he will also return to the court to play two matches on Rod Laver Arena.

Andy Murray had entrenched himself in a different sport before receiving a "surprise" call from Novak Djokovic, asking for his expertise at the Australian Open.

"I know this court well. I have never managed to win the title here and this man - indicating Djokovic - is the only one responsible. Now I am here to try to sabotage him so that he does not win another Australian Open!" said Murray before telling the story behind the new collaboration.

"Provided he’s giving his best effort and trying as hard as he can, I’m absolutely fine with him expressing himself." Read more at straitstimes.com.