Atletico Madrid have launched an appeal against the transfer ban imposed on the La Liga outfit by FIFA.
Earlier this month Atletico, alongside arch rivals Real Madrid, were hit with a two-window ban on registering new players after the duo were found to have broken regulations regarding signings under the age of 18.
Atletico were also fined 900,000 Swiss francs, with Real fined 360,000, although both clubs are allowed to sign new players this month.
The ban was set to come into action in the summer before being lifted in January 2017.
However, the appeal process is expected to be lengthy, meaning the clubs are likely to be able to also make new signings this summer.
A statement from Atletico read: "We consider that we have acted within the law in all cases.
"In addition, we request the probationary suspension of the sanction pending the outcome of the appeal."
Under FIFA rules, players under the age of 18 cannot be transferred to another country, except in in limited situations.
Barcelona failed in their appeal of a similar ban two years ago.