Barcelona sporting director Robert Fernandez defended Josep Maria Bartomeu after the club president came under fire again on Sunday (AEST).

A Lionel Messi hat-trick inspired Barca to a 5-0 win over Espanyol, but a section of fans at Camp Nou continued to call for the resignation of Bartomeu through its chants.

Bartomeu has been criticised in the wake of Neymar's world-record sale to Paris Saint-Germain, and Barca's struggles to find a replacement.

But Fernandez called for calm from supporters as he criticised the media, although he admitted it had been a tough period for the club.

"We have had a difficult month. The most important thing in these moments is to remain calm," he said.

"In complicated situations, with the summer we've had, calm is necessary. If we let time pass a little, we will see things differently. We respect all opinions, but the last two, three weeks have been complicated.

"The people that have had to explain things have not done it well. That includes me, among others, but also the media.

"There are things which aren't true. News has come out which isn't real and these things do damage and create unpleasant situations."

Barca's win over Espanyol was its third from as many league games, seeing it sit top of the table by two points as Real Madrid lost ground again with a draw against Levante.