Atletico currently sit third on the LaLiga table, nine points behind leaders Barcelona.
According to journalist Pedro Fullana, the Rojiblancos want to take advantage of the winter transfer window to secure the services of a new left-back.
Atlético are not satisfied with the performances of either Matteo Ruggeri nor Javi Galán and are already considering selling one of them to free up funds to recruit a new specialist.
"The clear objective is to improve the left-back position. They hope to offload Javi Galán, who is not in Diego Pablo Simeone's plans. If a significant offer comes in for Ruggeri, they wouldn't hesitate. Ruggeri could leave instead of Javi Galán to reinforce that position," Fullana stated.
He also said on Cadena SER: "If any offers come in for players who aren't indispensable, like Connor Gallagher, they'll be considered. There's also talk in England about Alexander Sorloth if a good offer comes in."
On Italy attacker Giacomo Raspadori, Fullana added: "As of today, Raspadori is the most likely to leave. He knows he needs to play to be in the World Cup squad and wants to be an important player for the Italian national team. Roma has already inquired about him, and several Italian clubs are interested.
"None have made much progress, but there's a lot of interest in signing Raspadori in Italy, and that option is being seriously considered."