Atletico Madrid have signed Juventus midfielder Tiago on loan for the rest of the season with a view to a permanent deal.
The former Chelsea player completed the switch on Friday after passing a medical at the Vicente Calderon.
But the 28-year-old Portugal international will not be unveiled by the Spanish side until Monday as he has returned to Italy for Juve's clash with AC Milan.
A statement on the Spanish club's official website said: "Atletico Madrid have reached an agreement with Juventus for the temporary signing of the player Tiago Cardoso Mendes, with the option to buy.
"The midfielder will be presented by club president Enrique Cerezo on Monday."
The Portugal international moved to Chelsea from Benfica in 2004 but left for Lyon after just one season at Stamford Bridge.
He then moved on to Juve in the summer of 2007 but has fallen down the pecking order with the Serie A giants this season, making just six starts in all competitions.
He has become Atletico's first signing this winter as the mid-table club bid to move up La Liga and progress in the Europa League.