Messi hat trick puts Barca in Liga lead

Lionel Messi scored the 38th hat trick of his Barcelona career as Ernesto Valverde's side thrashed Espanyol 5-0 in the Catalan derby at the Camp Nou.

Gerard Pique and Luis Suarez were also on target as Barca maintained their perfect start to the season, moving four points ahead of Real Madrid, who were held by Levante earlier in the day.

Messi opened the scoring when he received a pass from Ivan Rakitic in what appeared to be an offside position. With no call coming from the referee, Messi dribbled around a defender and fired home.

He got his second by sliding to redirect Jordi Alba's pass by goalkeeper Pau Lopez. Messi started the attack but lost the ball, only for it to take two deflections off defenders before falling to Alba in the area.

After Espanyol forward Pablo Piatti hit the post, Messi made it a treble with a left-footed strike to slot in another pass from Alba.

Dembele then came on moments later in the second half to a round of applause from his new supporters. Barcelona paid a club-record sum to Borussia Dortmund for the 20-year-old France forward. With add-ons, his transfer could reach 147 million euros (about $173 million).

He showed his speed when he raced down the right side on a quick counterattack and crossed for Suarez to score. Suarez was making his league debut this season after missing the first two matches with a leg injury.

Gerard Pique also scored for Barcelona, who now host Juventus in the Champions League on Tuesday.