Mark Hughes saluted penalty shoot-out hero Shay Given after the Republic of Ireland goalkeeper stopped two spot kicks to see City through to their first European quarter-final in 30 years.
Given, signed from Newcastle in January, recovered from the shock of conceding two goals in the last six minutes of normal time at Aalborg to make dramatic priceless saves from Thomas Augustinussen and Luton Shelton.
Hughes said: "Knowing Shay was between the sticks gave us confidence. The lads had belief that he would play a hand and save a penalty at some point."
Given was beaten by a cheeky dink from substitute Siyabonga Nomvethe in the shoot-out and Hughes added: "He was upset - he wanted to chase the guy!"
City had their second narrow scrape of the campaign in Denmark, and Hughes - whose side had deserved to win the first leg by more than 2-0 - admitted: "You scratch your head and wonder how the situation has developed.
"We don't do things easy. We were in control for the first hour and were looking for the goal that would have put the tie to bed. Once they got a foothold they played very well in the second half and at times we were under a lot of pressure.
"It should never have got to the situation it did, but we're very happy to come through. We'll take the win, and we're through to the quarter finals for the first time in a long time. We're in the hat for a major European tournament and there will be some bigger tests, but let's enjoy the moment.
"We didn't take Aalborg lightly. They showed their experience at times tonight. Maybe Lady Luck is smiling on us somewhat. We know that we can play better than we have tonight."
But there was no good fortune injury-wise. Stephen Ireland limped away with an ankle injury, Vincent Kompany is struggling for Sunday against Sunderland and Wayne Bridge might have a hamstring problem.