Barcelona defender Gerard Pique has been linked with a return to former club Manchester United.
The 25-year-old has been criticised over his recent form as Barca have fallen 13 points behind rivals Real Madrid in the race for the La Liga title.
United, who sold Pique in 2008, have been alerted over his potential availability, according to El Economista.
Chelsea are also thought to be interested in signing the Spanish international as they are expected to make big changes to their squad in the summer.
