Barcelona are tracking Manchester United midfielder Ander Herrera as a potential replacement for Xavi.
Barca, banned from last summer's transfer window, will be clear to buy again in January and are seeking a successor for Xavi, now of Qatar's Al Sadd.
El Mundo Deportivo says high on their shortlist is Herrera, who has struggled to nail down a regular first-team place at Old Trafford since joining from Athletic Bilbao in 2014.
His first-team opportunities were further hindered earlier this year when United snapped up Bastian Schweinsteiger and Morgan Schneiderlin.
Barca are also reportedly tracking Borussia Dortmund's Ilkay Gundogan, Anderlecht's Youri Tielemans, Ajax's Riechedly Bazoer, Juventus star Paul Pogba, PSG's Marco Verratti and Bayer Leverkusen's Lars Bender.