BBC tennis correspondent Russell Fuller assesses what Novak Djokovic's shock appointment of Andy Murray as coach could mean for both men.

The recently retired Andy Murray is going to team up with longtime rival Novak Djokovic as his coach, they both announced Saturday, with plans to prepare for — and work together through — the Australian Open in January.

Novak Djokovic cracked a hilarious joke after the news broke out of him adding Andy Murray for the Australian Open as he referenced to one of the Briton's post that came just hours after he retired.