Atletico, together with city rivals Real Madrid, were banned in July 2016 from registering players for two transfer windows and fined after a Fifa investigation concerning players aged under 18 who played in competitions for Atletico between 2007 and 2014, and Real from 2005 to 2014. Both sides failed in their initial appeals to Fifa, but Real had their ban halved by Cas, while Atletico's suspension was upheld on Thursday, although their fine was reduced. Atletico called the Cas ruling "unfair" and said it would cause "irreparable damage" to the club.
Later on Thursday, Griezmann posted a message on social media reading: "Now more than ever! #atleti #alltogether." He had previously told French television show Quotidien there was a "6/10" chance of joining Manchester United this summer. As Atletico cannot register new players again until 1 January 2018, it is anticipated they will offer Griezmann a new contract - his current deal includes a 100m euro (£86m) release clause.