FC Barcelona are interested in Borussia Dortmund full back Raphael Guerreiro this summer.
According to an exclusive in Catalan newspaper Diario Sport, Ernesto Valerde's side are in the market for a new left back – either as first choice, or as cover for Jordi Alba.
The Portuguese international has a year to go on his contract with the Bundesliga side, and he is reported to be considering his options after rejecting their initial offer, with the La Liga champions put on red alert.
The 25-year old is one of the highest rated left backs in world football, and he could be available for around €25m due to his contract situation with Lucien Favre's side.
Sport believe that the complications over the potential transfer of Ajax skipper Matthijs De Ligt to the Camp Nou, means that Valverde's side may be willing to abandon their original plan to sign a left back on a free transfer.
They have been linked with free agents Alberto Moreno and Filipe Luis, following their exits from Liverpool and Atletico Madrid respectively, but if the De Ligt deal does not come offer – there will be funds to move for Guerreiro.