Gerard Pique has revealed how earning the wrath of Roy Keane gave him an early insight into life at Manchester United.
Pique, who arrived at Old Trafford as a youngster from Barcelona, was preparing for a match in the dressing when his mobile phone began to ring.
Keane, who memorably lost his temper when he was Ipswich boss after a reporter's phone went off in a press conference, did not take kindly to the interruption and let Pique know his feelings.
And it is a dressing room dressing down the Spaniard, who returned to the Nou Camp in 2008, remembers well.
"Roy can't find where the noise is coming from. Now he's looking around the room like a maniac"
"One of my very first matches at Old Trafford, we were in the dressing room getting ready, and I was nervous as hell," he told The Players' Tribune.
"Imagine it - I'm 18 years old, and I'm sitting in that little dressing room putting on my socks next to Ruud van Nistelrooy, Ryan Giggs and Rio Ferdinand. I wanted to be invisible. I was thinking, 'Just do your job and go unnoticed'.
"So we're sitting there waiting for the gaffer (Alex Ferguson) to come in and speak to us, and I'm literally sitting right next to Roy Keane. The dressing room is so small that our legs are almost touching. There's no space at all.
"It's dead quiet. All of a sudden, you could hear this little vibration. Very soft. Roy is looking around the room.
"I realise it's me. It's my cell phone. I left it on vibrate, and it's in the pocket of my pants, stuffed in the clothes bag that's hanging right behind Roy's head.
"Roy can't find where the noise is coming from. Now he's looking around the room like a maniac.
"His eyes are darting everywhere, and he's trying to figure it out. You know the famous scene with Jack Nicholson in The Shining, when he bursts through the door? That's what he looked like.
"He screams out to everybody, 'Whose phone is that?!'. Silence. He asks again. Silence. He asks a third time. 'Whose. Bloody. F*****g. Phone. Is. That?!'
"Finally, I spoke up, like a little boy. Very softly, I said, 'I'm so sorry. It's mine."
"Roy lost his mind! He went nuts in front of everybody! It was incredible. I almost s**t myself. But it was a good lesson.
"Now, in 2018, everything is different. All these kids are on their iPhones before the matches. But back then, in 2006?
"It was a different world. You didn't do that. Especially not at United. Not in Roy's dressing room. It was one of a thousand mistakes that I made when I was at United."