Sir Alex Ferguson did not hold back in his autobiography when it came to Roy Keane, who was probably Fergie's top lieutenant during his tenure at Manchester United.
He calls him, among other things, "intimidating and ferocious." He says that Keano, "has the most savage tongue you can imagine. He can debilitate the most confident person in the world in seconds... It was frightening to watch."
As someone who shared a changing room with both of them in the early 1990s, I can confirm that most of Fergie’s character assessment of Roy Keane is 100 per cent true.
Keane back then was a very intimidating, confrontational man. Half the time, it appeared that he would look for reasons to start an argument.
And even if there was nothing about you at the time worth disagreeing over, if you were in the middle of getting changed and had hardly a stitch on, he’d find a way to start a row about your underwear.
But what hasn't been underscored as much as it should be - particularly in media appraisals of the book - is that as fiery as Keane was at the top of his flare, many of us actually found him to be a very decent, very approachable human being.
That he had that fire in his belly was simply a part of who he was. And it was a big reason he was as good as he was on the pitch, in his day.
If you think about the other ex-players Ferguson criticises, from the David Beckhams to the Ruud van Nistelrooys, none of them were afforded the leeway that Keane was. Fergie claims that Ruud and Becks had to go, “the moment they challenged the manager’s authority.”
And yet Keano was not what you’d call the perfect subordinate throughout his time at United.
Why do you think this is the case? It isn’t because Fergie was more intimidated by Keane than the others.
It’s because, as great as the Beckhams, the Van Nistelrooys, the Jaap Stams, the Paul Inces and other players eventually shown the door were, none of them were as indispensable to United at such a crucial time for the club as Roy.
Keane was Alex Ferguson’s top guy on the pitch as he turned four tough seasons at the beginning into a dominant dynasty of the 1990s. Had Sir Alex reacted to the first, second, third and so on instance of the Irishman being difficult to manage by offloading him, the United we all know today may not have been the force it was.
Yes, Beckham and co were huge losses, but Ferguson evolved the side and his management style to deal with those losses. Replacing Keane in his prime would have needed more than that.
Ferguson also says in the book that when he did let Keane go, it was the perfect time, mostly because his authority on the pitch was diminishing.
I couldn't agree more.
It was that on-pitch authority that allowed Keane to command clout at the training ground or stadium that was surpassed only by that of Fergie himself. Once that went, there was no need to cut him any slack.
It was then and only then, in the mid-2000s, that the book claims Keane was regarded by Sir Alex as having challenged authority, with the book claiming that Ferguson and his assistant Carlos Queiroz both decided that Keane had to go after giving an interview to MUTV in which he slated most of his team-mates.
But we all know from following the best and worst of Roy in his heyday that it was in no way his first offence, as it had been for everyone else who got the chop.
It goes to show exactly why Ferguson was as successful as he was. His philosophy is perfectly demonstrated when he says that Roberto Mancini "let himself down" by backing down in his spat with Carlos Tevez. That was the beginning of the end for the Manchester City boss, the book claims, because wilting to player power decides your fate as a coach.
Fergie never let that happen, though, and instead he got years of incredible service from the player. As it stands, Fergie’s handling of Keane may go down as one of the greatest examples of man-management in football.