The 17-year-old starlet enjoyed a dream debut for the Catalan giants when introduced off the bench in a home date with Athletic Club. Within 23 seconds of joining the action at Camp Nou on Sunday, Guiu netted what proved to be a match-winning goal.
With just his second touch as a senior star for the Blaugrana, Guiu hit the back of the net and wrapped up three points for the reigning Spanish champions.
He was mobbed by jubilant team-mates during and after a contest that has seen him follow in the illustrious footsteps of other La Masia academy graduates such as Lionel Messi, Andres Iniesta, Gavi and Lamine Yamal.
While taking in much deserved adulation at the final whistle against Athletic Club, Guiu was hit with a bizarre request from club colleague Cancelo.
The Portugal international, who is on loan at Barca from Premier League title holders Manchester City, told the talented teenager: “You have to buy us a dinner now. You have to buy us a dinner in McDonald’s.”
Guiu has been given his big break as Barcelona contend with a number of untimely injuries, with the promising forward showing that he boasts the potential to be a useful option for Xavi – another of those that knows all about the pressure of stepping out of the youth team and into the first-team fold.