The pair drew 0-0 at San Siro last Wednesday after a tight and turgid game in which the hosts arguably had the more clear-cut chances.
However, Iniesta is hoping that it will be a very different story at Camp Nou as he is anticipating a far more open encounter.
“We have to win, that’s the reality," the Spain international told reporters after his side's 2-0 La Liga win over Athletic Bilbao.
"At home, with our fans, we have to get to the next round and we must go into the match with confidence. We’ll see 90 thrilling minutes."
Iniesta opened the scoring in the Blaugrana's crucial victory over Athletic and the World Cup winner was buoyed by his side's performance against a side that he holds in the highest esteem.
“The game was very demanding," the midfielder mused. "I think the team played a very good match.
"Athletic forced all of our players - from the keeper to the forwards - to play well. They didn't create a lot of goalscoring chances, but they demanded a lot of us.
"We have to give value to this victory, because if you lower the intensity at any moment against Athletic, they roll right over you.
“We needed to win the three points today; that’s what’s really important. If we keep on winning all three points each week we’ll have a chance to win the title at the end of the season.”
Barca's victory means that they remain six points in arrears of leaders Real Madrid, with Los Blancos having routed Osasuna in Pamplona earlier in the day.