The home side dominated the possession in the first period, but could not make the breakthrough with the scores level at the interval.
Barca finally opened the scoring after 68 minutes courtesy of Alexis Sanchez, with that strike handing them all three points.
Read how it all unfolded in Sports Mole's minute-by-minute live commentary of the action below.
BARCELONA: Valdes; Alves, Pique, Mascherano, Montoya; Iniesta, Xavi, Busquets; Sanchez, Messi, Neymar
ESPANYOL: Casilla; Rodriguez, Sidnei, Moreno, Fuentes; Torje, Sanchez, Abraham, Lopez; Garcia, Bifouma