Mancini accepts the Carling Cup is still the most obvious route to an end to City's 36-year trophy drought.
At the time, Mancini and his team were devastated.
Now, he looks back with a positive attitude mixed in with the disappointment.
"Those games came at a very difficult moment for us, just as tomorrow's game does," he recalled. "The defeat was difficult to take because over the two games we played at the same level and deserved to take the tie into extra-time against Manchester United.
"But when I look back now it was still a very important experience for us because we produced two good performances against them."