Tainio linked up with Auxerre six years ago after undergoing a trial with The Red Devils as a 17-year-old.
The exciting midfielder claims United boss Sir Alex Ferguson wanted to bring him to Old Trafford after Tainio spent a year being groomed at Auxerre.
The switch ultimately failed to materialise but the 23-year-old has no regrets about failing to secure a move to the Premiership champions.
"I trained for two weeks with Man Utd and it was a great experience," revealed Tainio. "I played two games for the reserves and I scored four goals.
"I had to go back to Finland to complete my army service.
"I was supposed to go to Auxerre for a year and then move to Old Trafford. I talked with Sir Alex Ferguson and he wanted to sign me."
