United were left with just Marouane Fellaini to show for their deadline-day endeavours as a move for Herrera broke down with just hours to go.
The 24-year-old kept his counsel throughout the saga which saw three lawyers claiming to represent United show up at the Spanish league’s headquarters – apparently to pay the £31million release clause in the player’s contract.
United later claimed to have no knowledge of the three, and no deal could be reached with Athletic before the 11pm deadline.
And Herrera, speaking at a press conference reported on the club’s Twitter feed, insisted the lawyers were not acting on his behalf and said he did not get as far as talking personal terms.
“The only option, as the president said, was to pay my clause. I was never told United would pay the clause,” he said.
“At no time have either I or my agent reached an agreement with United.
“I’ve been silent because the important thing was (Sunday’s) game at Real Madrid. Today I’m here, with no problem, with the truth.
“I will continue to demonstrate my commitment to the club as I have since the first day I arrived. I speak for me. I do not speak of other cases. The club can confirm that my behaviour has been fantastic.
“I’m very flattered to see that one of the biggest clubs in the world, such as United, bid for me (but) I did not talk at any time with United. I’ve been very quiet.”