The legendary Scot brought the curtain down on his distinguished coaching career at the end of the 2012/13 campaign - with 26 years at Old Trafford bringing 38 major trophies, including 13 Premier League titles.
David Moyes was the man chosen as his successor, with United having been impressed by the job he oversaw at Everton.
Things have not gone entirely to plan for the new man at the helm, though, with United having suffered three defeats in their opening six top-flight fixtures to sit 12th in the table.
It has been suggested that Moyes, who signed a long-term contract upon his arrival, could already be on borrowed time, but Ferguson is confident fortunes will be reversed and has sought to bring an end to speculation suggesting he could be lured back to the dugout.
In an interview aired on American television network PBS, Ferguson said: "I'm not interested in managing again or getting myself worked up about Manchester United's results.
"United are in good hands with David Moyes. He will be fine. He's a good manager.
"You would be throwing your money down the drain if you put any money on me coming back as a manager.
"I made my decision. The timing was perfect. There is no way back for me now. I've got a new life. I want to go to the Kentucky Derby and the US Masters, the Melbourne Cup. I want to visit vineyards in Tuscany and France."
While ruling out a spectacular return to club management, Ferguson has revealed that Chelsea owner Roman Abramovich tried to take him to Stamford Bridge shortly after completing a takeover in 2003.
He added: "They used an agent to approach me when Abramovich first took over the club and I said, 'No chance'.
"I always come back to this point - why would you leave?"
Ferguson, who reiterated that Wayne Rooney did ask to leave United at the end of last season but has made a welcome return to form since failing to secure a summer switch, also lifted the lid on the techniques which helped to keep him at the top of his chosen profession for so long.
He said: "Never hold a grudge, it's very important.
"I always say to them at half-time, the last 15 minutes - throw the kitchen sink."