The Bianconeri won 3-0 in Turin in the first leg of their Champions League quarter-final tie, which means Barca have another mountain to climb.
Luis Enrique's side overcame a 4-0 deficit against Paris Saint-Germain in the last 16, winning the second leg 6-1 at the Camp Nou.
"We need to try and score as soon as possible and see how the game unfolds, be patient and know how to suffer, how to push when needed and try to make the most of our opportunities," Iniesta said during the pre-match press conference.
"In my opinion there's nothing else we can do. We can't get nervous if the goals don't come right away, they'll have to come, we'll need to work throughout the game and minimise their chances.
'The first leg was a bad result for us, because we didn't do things properly as everyone saw. Now the result is difficult to overturn, not least because of the opponents we're facing.
"That said, we have the potential and the players to turn around this elimination, or at least to try."