Barcelona home fans booed Javier Mascherano during their battling win over Real Betis. Barca struggled for form, but did just enough to earn the three points, much to the frustration of a section of the Nou Camp support.
Marca says Mascherano was the subject of their ire after making two serious mistakes in the space of just two minutes.
Later, more whistles could be heard as Betis players began dominating possession.
It has become noticeable this season that Barca's home support have become less forgiving of errors from some players, including Mascherano, Cesc Fabregas and Neymar.