Rodrigo García Lucas, Alvaro Reig Gurrea and Guillermo Gutiérrez were photographed entering the league's offices on Monday afternoon, with less than 12 hours to go in the transfer window. The three men represent the Spanish law firm Laffer, which oversaw Bayern Munich's successful move for Javi Martínez. That deal was completed by paying the buyout clause, against the wishes of Athletic Bilbao.
It is understood the lawyers had been instructed by United to attempt to find a resolution to the transfer and, according to sources at the Spanish league, did so with the formal authorisation from Manchester United.
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They later briefed United as to the difficulties of closing a deal so late in the window; they could not guarantee that it would be completed successfully and without subsequent risks.
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Faced with the uncertainty and potentially extra costs involved in tax, United decided not to proceed, thereby forcing Herrera to stay in Spain, the sources state. United had told the midfielder to be prepared in the event of a deal going through. Once the deal collapsed, United claimed that the three men had nothing to do with them.