Ibrahimovic joined the Blaugrana from Inter as part of a transfer totalling an estimated €69.6 million but he lasted one season in Catalunya before returning to Italy to link up with the Rossoneri, initially on loan before completing a permanent switch to San Siro last summer.
The 30-year-old disclosed the full extent of the breakdown of his working relationship with Guardiola in his autobiography last year but the Barca coach remains reluctant to be drawn on his falling out with Ibrahimovic and instead praised the ability of an in-form forward that the La Liga champions must figure out a way to nullify in next week's Champions League first-leg clash meeting with the Rossoneri.
"Ibrahimovic is a player that plays at very, very high level," the former Spain international told reporters at a press conference on Monday evening. "He's a leader at AC Milan."
Meanwhile, Guardiola had words of encouragement for winger Pedro, who, after a rapid rise to the top of the game after being formally promoted to the Barca senior side from the B team in 2009, has seen little game time this season.
"It's thanks to the effort that Pedro puts in that the rest of the players can play like they do," the 41-year-old argued. "Pedro runs for three others; that's his great virtue.
"He knows exactly what he has to do. He's level-headed in that way. I just want him to keep doing what he's always done.
"If he's struggling more than usual this, it's because he's had a few injury setbacks which have affected his consistency.
"If you have an explosive debut season and continue that way for two seasons, it's quite normal that a time will come when you reach that kind of plateau and stability."
Barcelona are in La Liga action against Granada on Tuesday, with the game at Camp Nou getting underway at 21:00CET.
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