The Swedish winger felt the need to apologise to the United manager because he had barely featured during the previous season due to a succession of injuries.
However, the 39-year-old has praised Ferguson for the way that he dealt with him during his three-year stint at Old Trafford.
"I said sorry to Sir Alex because I felt like I'd let him down and he just said, 'Jesper, don't worry. This is the nature of football. You helped us to win the Treble and we're very grateful for that," he told Inside United.
"Those words lifted a stone from my heart. I'd not played for two years and I felt guilty for taking up the club's time and money. But he helped me realise I didn't have to feel bad.
"I think that says a lot about him. The reason he's such a great manager is because of the way he treats people. Sometimes people forget there's a person behind his tough persona."
After United, Blomqvist had spells with Everton and Charlton Athletic before returning to his homeland.