Zola acknowledges the magnitude of the test Chelsea face, with Barca boasting a formidable home record this term, but is quietly confident that the Blues can pull off a shock result.
"It's not going to be easy. Playing in Barcelona is a tough game. But Chelsea are a strong team, with good players," he told Omnisport. "I think they can go there and surprise Barcelona, they have the ability to do that.
"Chelsea have the type of players Barcelona don't like very much, so in my opinion, it's still an open game. They will have to defend well. The first leg was 1-1; Barcelona will want to try to win the game [rather than rely on the away goal advantage].
"I'm sure they will want to be safe. If Chelsea defend well first, then they can use the counter as they can do really well. I think they stand a very good chance."
Zola found the net for Chelsea in a 3-1 win over Barcelona in a knockout-round clash 18 years ago, but still ended up crashing out on away goals.