Barca won the first match at Camp Nou 5-1 and are sitting in pole position to reach the semi-finals, forcing Fernandinho to admit to fifa.com that the task facing his side is verging on the impossible.
The Brazilian said: "Eliminating Barcelona is extremely difficult. We need to beat them 4-0 and I don’t even know who were the last team to do that. But we’re going to try to pick up a win at the very least.
"Even if we don’t manage to knock them out, we’re going to at least try and exit the Champions League with a win in front of our home fans. That would give them something to be pleased about. It’s about playing for Shakhtar’s pride."
Fernandinho hopes that the weekend visit to the Santiago Bernabeu to face rivals Real Madrid may force the Blaugrana to lose focus.
"We need a real miracle," he added, "but I’ve not given up hope. They’ve got an important game against Real Madrid next weekend and, who knows, they might rest a few players which would work in our favour."