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.
Barcelona hit seven in Racing Santander rout
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.
"It's always important to think you need to improve in some way," Raphinha told DAZN.
"So I'll never tell you I'm at my best level, because... I always try to improve as much as I can, and give more to the team than I am given.
