United's spluttering opening to the new season caught up with them at Old Trafford on Saturday. For the fifth time in six Barclays Premier League outings, they fell behind.
But against a speedy and durable Tottenham team, Ferguson's team left themselves too much to do and slipped to their second defeat of the campaign.
While praising United's second-half performance, Ferguson was furious with what went on before the break.
It followed on from similar lacklustre displays earlier in the season, particularly at Southampton and Liverpool.
And, speaking ahead of tonight's Champions League clash with CFR Cluj in Romania, Ferguson has vowed it will not continue.
"We were well off the pace of the game. I don't think we won a tackle in the first half," said the United boss.
"The second half was probably our best perfor-mance of the season.
"When you consider the first half against Southampton, the first half at Liverpool and first half on Saturday, we have some work to do.
"You have to be concerned losing goals the way we did. It's not planned but I think it will be the last.
"After the first half on Saturday I had plenty of concerns.
"I hope it's an awareness thing because we faced this situation at the end of October last season, and from then on when Jonny Evans and Rio Ferdinand played together consistently we played better."