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.

All eyes will be on Andy Murray and Novak Djokovic over the next fortnight at the Australian Open as the Scot sets his former rival a new challenge, having crowned him tennis' 'GOAT'

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.