His last Grand Slam tournament victory was in 1984; he retired from the professional circuit in 1992; he has children who are older than he was when people first noticed him in the late 1970s. But John McEnroe remains one of the most popular, and interesting, people in tennis. Glimpses of him playing – in YouTube clips or even on the slowed-down seniors circuit – can spark nostalgia for the way the game used to be. On the eve of another Australian Open, a tournament in which he experienced both highs and lows, we catch up with the still stormy court genius.