The pair worked together at Camp Nou during the 2009-10 season, before the Sweden international moved to Milan after relations with the current Bayern Munich manager broke down.
However, in his autobiography, I am Zlatan Ibrahimovic, the 31-year-old described an exchange in the dressing room after a 4-1 win at Villarreal - a game in which he was brought on for the last five minutes.
"I was seething inside, not because I was on the bench. I can deal with that, if the manager is man enough to say: 'You're not good enough, Zlatan. You haven't made the grade'," The Daily Mail revealed.
"Guardiola didn’t say a word, not a peep, and now I’d had enough. I could feel it in my whole body, and if I’d been Guardiola, I would’ve been scared.
"There was the metal box where we put our kit from the match, and I was staring at that box. Then I gave it a kick. I think it went flying about three metres, but I wasn’t finished yet. Not by a long chalk.
"I completely lost it, and you might have expected Guardiola to say a few words in response, but he’s a spineless coward. He just picked up the metal box, like a little caretaker."
Ibrahimovic also criticised Barcelona as a club, describing it as "like being back at school", due to a lack of charisma among the ranks.
"I’d already got the impression that Barcelona was a little like being back at Ajax, like being back at school," he continued.
"None of the lads acted like superstars, which was strange. (Lionel) Messi, Xavi, (Andres) Iniesta, the whole gang - they were like schoolboys. The best footballers in the world stood there with their heads bowed, and I didn’t understand any of it. It was ridiculous.
"Everyone did as they were told. I didn’t fit in, not at all. I thought, just enjoy the opportunity, don’t confirm their prejudices. So I started to adapt and blend in. I became way too nice. It was mental.
"I said what I thought people wanted me to say. It was completely messed up. I drove the club’s Audi and stood there and nodded my head. I hardly even yelled at my team-mates any more. I was boring. Zlatan was no longer Zlatan."
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