The Spanish football league have confirmed they have extended the current transfer window by 24 hours.
Spanish clubs will now have until midnight on January 31 to sign new players.
They were given permission to do so by FIFA, who granted a request by the Spanish Football association to extend the deadline to match other countries.
Meanwhile, Atletico Madrid have rubbished reports they have agreed a deal for the transfer of striker Sergio Aguero to city rivals Real Madrid.
Spanish newspaper 20 minutos claimed sources close to Madrid had revealed an agreement had been reached with Atletico and the signed paperwork handed in to lawyers.
However, Atletico insist no such deal exists.
''At no point have Atletico Madrid had either formal or informal contact, much less reached an agreement or signed any contract with Real Madrid for the sale of Sergio Leonel Aguero nor of any other player,'' read a statement on the Atletico website.
''The player has a valid contract until the 2011/12 season, and a buy-out clause for 60m euros.
''The player has demonstrated on numerous occasions his commitment to the club, for which it is the intention of both parties to remain united.
''It is the interest of the club to achieve and reach each year our set sporting targets and take the team far in each competition, and for that we are relying on the aforementioned player.''