There have been theories thrown out there as to why Djokovic made his coaching decision, but seven-time major champion John McEnroe offered a pretty hilarious theory this weekend.

John McEnroe saw the funny side of Andy Murray joining Novak Djokovic's coaching team, floating the idea of Murray returning with fresh knowledge of his rival.

John McEnroe has joked that Andy Murray agreed to coach Novak Djokovic so he can discover ways to beat the Serbian. The American teased that Murray would then come out of retirement and use the knowledge to get the better of the 24-time Grand Slam champion in a showdown on the court.