Ousmane Dembele made his Barcelona debut, but it was Lionel Messi's night as his hat-trick demolished Espanyol 5-0 in the Catalan derby on Saturday.
Dembele came on as a substitute in the second half and teed up Luis Suarez for a comeback finish at the death, but the damage had long been done by Messi, who helped himself to a treble of strikes.
The hosts dominated possession in the first half but had only the Uruguayan’s free kick, which forced a save from Pau Lopez, to show for in the opening 20 minutes.
However, they refused to abandon their patient probing and Messi took his time to pick his spot past Pau from near the penalty spot, although the Argentine was half-a-yard offside.
Ivan Rakitic then drove into the box and played a one-two with Messi, before curling a shot on target, but Pau managed to push it away.
Messi soon grabbed his and the Blaugrana’s second goal, sliding home a cutback from the electric Jordi Alba. The No 10 appeared to be in for a quick-fire hat-trick, only to be denied by Marc Hermosa’s last-ditch tackle.
Espanyol, for their part, could’ve pulled a goal back, but Piatti drilled his shot onto Marc-Andre ter Stegen’s right-hand post, with the goalkeeper well beaten.
Suarez was laid off by Deulofeu at Pau’s near post not long afte the restart, but the goalkeeper kept out the striker’s finish from point-blank range.
Piatti, however, should’ve taken advantage of a mix-up between Ter Stegen and Alba in Barca’s penalty area, but the Argentine’s lobbed finish went wide.
A low cross was then expertly controlled by Baptistao in the box again, but his half-volley took a deflection off Samuel Umtiti in the nick of time.
From there, Barca never looked back. Messi ran onto Rakitic’s clipped ball and pulled back for Suarez at the byline, but the unbalanced No 9 swiped his volley over from a yard out.
Fantastic geometry from the home side’s forwards saw Messi and Suarez interchange, before Deulofeu had to intervene and squared for the little magician, who coolly swept home for his hat-trick.
That proved to be the cue for Dembele’s introduction, marked by the Barca fans chanting his name in unison.
The record signing wasted little time in displaying his ability to run at pace with both feet, but instead of laying off Suarez, he was dispossessed and Nelson Semedo was offside when he met the ricochet.
Moments after fellow substitute Paulinho came a whisker away from poking in a diagonal ball for 4-0, Didac Vila’s rocket was tipped over by Ter Stegen.
Nonetheless, Pique’s towering header with three minutes to go put the Blaugrana four to the good, before Dembele broke clear down the far right and squared the ball on a silver platter for Suarez to tap in.