Manchester City midfielder Ilkay Gundogan revealed he came close to signing for cross-town rivals United before the start of the 2014-15 season.
The Germany international - currently recovering from a dislocated kneecap - said he held talks with United last summer.
However, Dortmund fans turned on their former hero, accusing him of being a mercenary as rumours intensified of a switch to Old Trafford.
And Gundogan revealed the conditions were not right for him to leave as he eventually chose to sign a one-year extension with Dortmund to ensure they received a fee for his transfer.
"Maybe last year it [a move to United] was close, but not everything happened like I wanted it to," the 25-year-old told Sport360.
"Maybe it was not the right moment and at the end we decided to stay and renew my contract, to extend for one more year.
"We always had the conversation with Dortmund and agreed that if I left, I will not leave for free, for zero.
"So I renewed my contract and now this year everyone is lucky and happy how it came to an end."
In the end, it was City who paid for the midfielder, who could become a key part of Pep Guardiola's plans.
"I recognised over the last few months that I needed a change, to start from zero, to prove myself again," Gundogan continued.
"Which is why I'm really happy to be here, to have the chance to work with Guardiola and this wonderful club."
- Goal