John McEnroe has always been outspoken. He was outspoken on the court as a player and he's been consistently outspoken from the commentary box.
In an interview with the BBC, the 56-year-old American, who won seven Grand Slam singles titles, gave me his latest ideas for revitalising tennis and also talks politics and social welfare.
Specifically, he thinks Serena Williams should become president of the United States - with him as vice-president, of course...
"I would have thought that a woman would have become president before a black man. What I think is frustrating for Americans is that it feels like more was going to change with Obama. So maybe we need a black woman - maybe we get Serena to run."
McEnroe the social reformer
McEnroe admits quite happily that it is "against my nature to try and work within a system and be a politician".
But there is plenty he would like to change. It frustrates him that tennis remains a predominantly white sport and that families are being priced out of the world's most expensive capitals.
"It seems like the richer you are, the more chance you have of paying less tax. Why have real estate prices gone absolutely insane in London and New York?"
It didn't take long for me to realise that this was a rhetorical question.
"Because there's a bunch of foreigners that want to park their money somewhere - in a lot of cases, for mysterious reasons - and yet they are paying all types of crazy money and that has forced the average person out," he continued.
|JP McEnroe Grand Slam titles|
|Wimbledon singles champion 1981, 1983, 1984|
|US Open singles champion 1979, 1980, 1981, 1984|
|Wimbledon doubles champion 1979, 1981, 1983, 1984, 1992|
|US Open doubles champion 1979, 1981, 1983, 1989|
"You need a thriving middle class and if you don't have that, I think it becomes something different than it was ever planned to be.
"The way things are going, in 20 years you are going to have to go onto the Triborough Bridge [in New York] and show someone a card that says your net worth is at least a million dollars - or they're not even going to let you in the place."
Why are tennis players expected to behave as if it was 1955?
McEnroe's views on the future of tennis are especially relevant, as he is a member of the ATP's Legends Advisory Board, which has been tasked with coming up with ideas to make the sport even more appealing in future.
The ATP's executive chairman Chris Kermode should expect to do a lot of listening when he meets McEnroe for lunch in the next couple of days.
"When I came on the tour," McEnroe continued, "I thought, why don't they treat tennis players the same way they look at football players? Because I've got news for you, when they are on the pitch, they are not saying 'Hello, how are you?' out there.
"Even the cricketers are probably going at each other - something tells me they are trash talking a bit. It was totally like tennis players have to act a certain way - well, why do we have to act a certain way they acted 60 years ago? The women got the right to vote in 1920 in America - does that mean we should think the way people thought in 1910?"
Do we really need line judges?
And in a similar vein, McEnroe thinks the sport would be a lot more exciting if players were asked to call their own lines. It will be trialled on the US seniors' circuit over the next couple of months.
"Murray, you bum, you just cheated Nadal, and vice versa," McEnroe imagines the crowd shouting out if the implausible suggestion ever became official policy.
"It would have this incredible excitement and you wouldn't know what was going to happen and that is part of what makes sport so great.
"Things would get a whole lot more intense, and I'm telling you, 30% more exciting. We've got to think ahead 10 or 20 years from where tennis is now, and think bigger picture to get back in the mix along with the top sports."
Scrap the warm-up
McEnroe will have much more support for his desire to abolish the five-minute knock-up that precedes every match - as it can break the tension of the occasion. Instead, he would take a leaf out of boxing's book.
"Boxers come out into the ring," he said. "They are about to tear each other's head off and possibly your life is at stake. They don't go out there and tap each other, hit each other: for that first punch, your anticipation is 'Wow!'"
Introduce a deciding set tie-break in every Grand Slam
The US Open is currently the only one of the four Grand Slams to allow a final set tie-break.
McEnroe is convinced that Wimbledon, Roland Garros and the Australian Open should follow suit - arguing it is inhumane to expect players to continue past six-all in the fifth set.
"These people play four or five hours and is it not enough that they've got to go to six-all in the fifth: after all that time, the stress and the fact that they've got to go out and potentially play four, five or six more matches?"
In the spirit of compromise - could he really become a consensus politician? - McEnroe suggests a final set tie-break could kick in at 10-all, or even 15-all, but is adamant that he never wants to see a repeat of John Isner's 70-68 final set win over Nicolas Mahut at Wimbledon 2010.
"I think it was the perfect time to change the rule that day. Don't ever, ever, as long as we have a sport called tennis, put two people through that again. Did you see him the next day? The guy looked like a statue. He couldn't even take a seat. Laughable. Do we have to have people endure this hell, the torture, where these guys weren't the same people for six months?"
Boris Becker, Mats Wilander, Lleyton Hewitt and Carlos Moya are the other members of the Legends Advisory Board. They will do well to get a word in edgeways.
Download the podcast to listen to the whole interview with John McEnroe.