The Premier League champions appeared to have secured their place in the final of the competition as the second leg at the Bernabeu ticked into the 90th minute, with City 1-0 up on the night and leading the tie 5-3 on aggregate.
But a late double from Rodrygo sent the game to extra-time, and from there Karim Benzema’s 93rd minute penalty finished a remarkable turnaround that saw Real win 3-1 at home and 6-5 over two legs.
It also meant City, who had controlled large parts of the game, conceded three in just 11 minutes.
Speaking after the game, Ferdinand implied City were overwhelmed by the big stage and failed to react calmly to conceding the first goal of the night.
“Whether it’s concentration, energy levels, mentaly being prepared for this type of occasion or not being prepared for what we felt in this stadium.
“This stadium was rocking. If it had a roof it would have come off. Not being prepared for that, you can be stunned and the game passes you by. It seemed like that happened.
“It was just the energy in the stadium,” he continued. “I thought they [Real] would have a chance. You can’t understand until you get into a stadium like this and sometimes when you’re on the pitch as a player, what that can do.
“It’s about having that sense of clarity in those moments. Once the game starts getting pulled away from you, it can get fuzzy.
“You can panic and make rash decisions that you wouldn’t necessarily make when the game is under control. That separates the top teams and Real do it year in, year out.”