Ferguson insists Chelsea manager Mourinho does not know what he is talking about and rapped: "I have signed many players in the 20 years I have been here and there was more pressure on me when I was signing players at the start of my time at Old Trafford.
"Before we won the championship, every player we signed saw me asked if this was the final piece in the jigsaw.
"We signed Viv Anderson, Brian McClair, Steve Bruce and Mark Hughes and every time it was 'Is this the final piece?'
"That remained the same until we had won the League.
"After we had won it, it was not an issue any more as to who you signed, as it was an upward trend at the club. The pressure was off."
Mourinho claimed earlier this summer the heat was all on the Scot after his big signings - and he was at it again yesterday.
He said: "When Chelsea were the top spenders in previous years, everyone talked about it all the time and put pressure on us. If the other managers are now treated the same, they will feel that pressure."