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.

Novak Djokovic was left feeling embarrassed as he was put on the spot in a quiz about his new coach, Andy Murray. The 24-time Major champion recently added his old rival to his team and Murray has joined him in Melbourne for the Australian Open.

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.