Hansi Flick’s league leaders preserved their 100 percent record with a thumping victory over their promoted opponents, moving three points clear of Real Madrid.
Joao Cancelo, Gabriel Jesus and Lamine Yamal also scored for the unstoppable Catalan giants, who have netted 33 goals in seven games across all competitions.
With lightning flashing above Camp Nou, Barca started at rapid pace and took the lead with a thunderbolt from Cancelo.
The defender crashed a shot in off the crossbar from long range in the eighth minute to get Flick’s side up and running.
Dani Olmo twice came close before Raphinha won and converted a penalty for Barca’s second.
The Brazilian was clumsily brought down by Pedro Felipe and thrashed the spot-kick into the bottom right corner.
Racing Santander pulled one back when Maguette Gueye barged his way through and produced a neat finish to beat Barca goalkeeper Joan Garcia.
However it proved only brief respite for the visitors, with Cancelo provoking the third with another long-range effort which deflected in off Asier Villalibre.
Raphinha, thriving playing as Barca’s centre-forward, bagged Barca’s fourth after he was played in on goal by Olmo.
Teenage star Yamal should have added a fifth after the electric Karim Adeyemi was brought down in the box, but Julen Agirrezabala saved his penalty.
Barca reserve goalkeeper Wojciech Szczesny replaced Garcia at half-time after the Spain international appeared to hurt himself while slipping as he went to get the ball.
Yamal hit the post and later had a goal ruled out for offside, as the youngster suffered a more frustrating night than some of his colleagues.
In the second half Yassir Zabiri pulled another back for Racing after a dreadful error from Szczesny, who tried and failed to dribble the ball.
Zabiri tackled him to score. Barcelona’s fifth arrived almost immediately with another penalty after Adeyemi was brought down.
Raphinha completed his hat-trick from the spot for his ninth league goal, extending his lead as the league’s top goalscorer.
He was replaced by his compatriot Gabriel Jesus, who added the sixth with a sharp finish into the top corner after being played in by Yamal.
The winger eventually got his goal when Adeyemi roared down the left wing and set him up for Barca’s seventh and final goal. (AFP)
