Novak Djokovic and Andy Murray faced each other 36 times throughout their tennis careers, mostly in finals and often at the business end of a grand slam. But at this year’s Australian Open, their decades-long rivalry has taken an unexpected turn.

MELBOURNE, Australia — 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. Yet they've never been able to talk shop and freely trade all sorts of thoughts — about tennis and otherwise — until now.