Antoine Griezmann was on the scoresheet for the third consecutive game as Barcelona maintained their 100 per cent record in Group G with a comprehensive victory at Ferencvaros.
The France international netted in the recent 4-0 victories over Dinamo Kiev and Osasuna, and in the absence of the rested Lionel Messi he opened the scoring at Puskas Arena with just 14 minutes on the clock, converting from Jordi Alba's cross to spark a flurry of first-half goals for Ronald Koeman's side.
Six minutes later Martin Braithwaite doubled Barcelona's advantage, steering the ball home on the slide after reacting quickest to Ousmane Dembele's cross.
Creator Dembele turned goalscorer as the 23-year-old scored from the penalty spot after Braithwaite was upended by Abraham Frimpong, as Barcelona were out of sight by the half-hour mark.
With the game put to bed, Barcelona took their foot off the gas after the restart, introducing more young talents such as Riqui Puig and Konrad De La Fuente. A couple of half-chances from Dembele and a Miralem Pjanic shot was the closest they went to extending their lead, as Ferencvaros managed to stop the rot.
Having already sealed their place in the knockout stages before kick-off, Barcelona will now meet second-placed Juventus next week to determine who finishes top of the group after the Italian champions defeated Dinamo Kiev 3-0.