The holders managed to secure a 0-0 draw at the San Siro last Wednesday but the Barcelona manager remains wary of Milan’s aerial threat, and in particular Ibrahimović’s ability.
The 30-year-old Swedish striker joined Barcelona in 2009 but returned to Italy after a difficult season in La Liga, joining Milan on loan before sealing a permanent move.
“Milan are capable of dominating the game and generating dangerous situations,” Guardiola said.
“They have a very strong counterattack and their players reach the opposition penalty box very easily.
“We need a ladder to stop a player like Zlatan Ibrahimović because he’s so tall.
“If it’s a high ball we know it’s for Ibrahimović because of his height. We will try therefore to keep him away from the box.”
Guardiola added: “The situation is simple: the winner will be in the semi-finals.
“We have to think that Milan will score and they are capable enough of scoring at least one goal.
“We have to generate as much attacking momentum and danger as possible.
“I think they could score more than one goal, so we have to find the way to score more.”
Lionel Messi became Barcelona’s record goal scorer in March and the 24-year-old has netted a staggering 236 goals for the Catalan outfit.
But Messi has only struck once against Italian sides in Europe – an unfavourable record Guardiola is convinced Messi can change tonight.
“If you say that Messi doesn’t score much against Italian teams, then you know what happens: he will score lots,” added the Barca boss.
• Barcelona are unbeaten in 14 home fixtures dating back to October 2009, with 12 wins and two draws at the Camp Nou since then, including the 7-1 defeat of Bayer 04 Leverkusen in the last round.
• Seven-times winners AC Milan have won 11 and lost three of the 14 quarter-finals they have contested.
• Barcelona have won their last five quarter-finals – four in a row between 2008 and 2011 – and another in 2006 – their last defeat at this stage was against Juventus in 2003.
• AC Milan have yet to win away in the Champions League this season, posting three draws before the 3-0 loss at Arsenal FC in the last 16.
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