Atletico Madrid have announced the signing of Augusto Fernandez from fellow La Liga side Celta Vigo.
The Argentina international midfielder has signed a three-and-a-half year contract with Atleti until the end of the 2018-19 season.
Atletico sporting director Jose Luis Caminero told the club website: "He's a player of proven experience in the league that will bring quality and competition to a great midfield such as ours."
Fernandez leaves Celta having made 114 La Liga appearances in three-and-a-half seasons for Os Celestes.