Hint: It didn't turn out well for Gary Neville.
Former Manchester United defender Gary Neville has always seemed a brave chap, but perhaps not this brave.
The pundit played under the legendary Sir Alex Ferguson all of his career, so he must have known exactly how the manager would react to being disrespected.
That didn't stop him from telling the Scot to 'f**k off', though; and he even found the gonads to do it twice.
"The biggest telling off that I ever got [from Ferguson] was telling him to 'f*** off' at the end of a game in Lille," Neville said in an exclusive interview with Jonathan Shrager that you can watch below.
"He fined me a week's wages and battered me after the match.
"I did it again the day after in his office and then he basically proceeded to leave me out for the next two weeks. He put me on the bench.
"I spent the next 15 minutes of the match [against Lille] thinking, 'I'm done, I'm done, I'm done'."