Pep Guardiola is wary of the aerial threat of Zlatan Ibrahimovic when Barcelona play out their Champions League quarter-final second leg at Camp Nou on Tuesday night.
Barca host Milan having been held to a 0-0 stalemate in their first meeting last week, with a place in the last four against either Chelsea or Benfica at stake.
Ibrahimovic, 30, struggled to make his mark at Barca before moving on to Milan, but Guardiola has warned his players of the Sweden international's attacking qualities.
"We need a ladder to stop a player like Zlatan Ibrahimovic because he's so tall," Guardiola said at a press conference.
"If it's a high ball we know it's for Ibrahimovic because of his height. We will try therefore to keep him away from the box."
Meanwhile, Ibrahimovic has offered his opinion that Barca's Messi is a better player than Real Madrid forward Cristiano Ronaldo.
Messi has scored 58 goals for club and country this season while Ronaldo boasts the same tally, leading to debate over which of their pair is football's current greatest.
"Leo Messi is all talent, while Cristiano Ronaldo is the product of much training," Ibrahimovic told TV3.
"Messi does not need his right foot, though. He only uses the left and he's still the best in the world! Imagine if he also used his right foot ... then we [Milan] would have serious problems!"