Manchester United have been alerted to the fact that Real Madrid may make another bid to sign goalkeeper David de Gea next summer after the Court of Arbitration for Sport halved the European champions' two-window transfer ban on appeal.
The Spanish giants were sanctioned by FIFA for signing under-age players from abroad earlier this year.
Los Blancos and their fierce rivals Atletico Madrid were originally punished for multiple breaches of global football's rules on the transfer of under-18s in January and both failed in appeals to FIFA in September.
But now sport's highest court has partially upheld an appeal from Real, which means the current leaders of La Liga cannot sign any players in next month's transfer window but will be free to do so in the main summer transfer window.
The club's £283,000 fine has also been reduced to £189,000.
It leaves them free once again to pursue De Gea, who they almost signed on transfer deadline day in the summer of 2015, with the documentation arriving too late to be processed.
De Gea signed a new deal at United shortly after which runs until the summer of 2019, but Real are prepared to break the bank for the 26-year-old who is widely regarded as being one of the best goalkeepers in the world.
If United fail to make the Champions League again this season, the Spanish international may be to tempted to move back to his homeland.
FIFA's investigation into the Madrid clubs uncovered several incidences of wrongdoing between 2007 and 2014 at Atletico, with Real's rules breaches coming between 2005 and 2014. Atletico were adjudged to have broken the rules more frequently, however, a fact reflected in their £708,000 fine.