I did not expect that, he said and for those involved in Tuesday's Upton Park humiliation the warning signs are clear.
The last time United suffered an embarrassing exit in this competition - a 2-0 defeat at home to Coventry in the autumn of 2007 Ferguson's response was ominously similar.
I did not expect that at all, he said after two Michael Mifsud goals stunned Old Trafford. I am not interested in giving reasons or mitigating circumstances. It was just a very bad performance.
We have trumpeted these young lads a lot, so what has happened was a big shock for us all.
Dramatic
Those lads included Phil Bardsley, Danny Simpson, Fraizer Campbell and Chris Eagles all of whom were subsequently ushered out of the door.
Ferguson's reaction to Tuesday's 4-0 defeat at West Ham might not be so dramatic but the fate of those involved in the Coventry clash will serve as a warning.
As committed as the United manager is to developing youth, he is every bit as ruthless if he believes they are not up to the task of making it at Old Trafford.
He said his latest crop of youngsters will remember Tuesday night. So will he.
As much as he took the blame for his Upton Park selection, it was a line-up that he fully expected to secure victory and a place in the semi-final.
Chris Smalling, Jonny Evans, Fabio, Anderson, Javier Hernandez, Gabriel Obertan and Bebe may be young but have all been trusted in the Champions League.
So Ferguson's claim that his side was too inexperienced to cope with West Ham's onslaught and the typical intensity of Upton Park was fundamentally flawed.
Ferguson's success over 24 years at United has not only been achieved because of his ability to nurture talent, but also his ruthlessness in knowing when to cut it loose.
Context
And even if Tuesday's defeat must be taken in context United remain at the top of the Premier League and through to knockout stage of the Champions League he has made it clear that he is in the process of building his next generation.
It has been the performances of Evans, Danny Welbeck, Darron Gibson, Federico Macheda and the Da Silvas in this competition over the last two years that have given him the belief that he has crop of talent that can become fixtures at Old Trafford.
But as heartened as he has been by back-to-back Carling Cup successes over the past two years, this year's exit will have been a rude awakening.
Ryan Giggs says the challenge now is to put the result behind them starting with Saturday's trip to Blackpool.
Disappointment can help you, he said. It doesn't feel good at the moment, but hopefully the young players can learn from it.
Next time they're playing they'll be determined to improve their performance and get a better result.
We're Manchester United and have to rise above disappointment. You have to carry on, keep playing football and not let your head drop."
Do you think any of United's youngsters are in danger of being cut loose? Have your say.
Source: Manchester Evening News
Source: M.E.N.