United launched a late attempt to buy the Tottenham playmaker before the Premier League transfer window closed last Thursday.
Eriksen only has a year left to run on his Spurs contract and is unlikely to sign fresh terms in north London.
However, the Denmark international turned down the chance to join United because he wants to play in La Liga.
Eriksen was linked with Real Madrid earlier in the summer, but Zinedine Zidane's side have since turned their attention to other transfer targets.
Spanish clubs have until September 2 to complete their business before their window closes.
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