Atletico Madrid have made Joao Felix, Matheus Cunha, Felipe and Mario Hermoso available for transfer in the January market as the LaLiga club look to balance their books by moving on between three and five players, sources have told ESPN.
Atletico's finances were hit by their early elimination from the Champions League -- finishing bottom of group B behind FC Porto, Club Brugge and Bayer Leverkusen -- and missing out on a Europa League run which would have recouped some of that lost income.
They are currently fifth in LaLiga, level on points with Athletic Club and Real Betis in the race for the top four.
Sources said Atletico believed that their planned January business, coupled with qualification for next season's Champions League, would help get the club's finances back on track.
Joao Felix joined Atletico from Benfica for €127 million in July 2019 as one of the most highly rated teenagers in European football, intended as a replacement for the Barcelona-bound Antoine Griezmann.
The Portugal forward, 23, has struggled to make a consistent impact at the Metropolitano stadium, scoring 33 goals and providing 18 assists in 129 competitive appearances for the club.