Ousmane Dembele's brace and a second-half goal from Lionel Messi ensured Barcelona beat Levante 3-0 at Camp Nou, as they comfortably overturned a first-leg deficit to progress to the Copa del Rey quarter-finals.
Trailing 2-1 in the tie, Ernesto Valverde handed a start to Messi and he played a part in both of Dembele's goals before making sure of the aggregate victory by finding the net himself just after the break.
However, Levante president Quico Catalan had already said his club will challenge Barcelona's progression, with reports in Spain suggesting the LaLiga champions fielded an ineligible player in the previous meeting.
Defender Chumi featured in that game, even though he had been due to serve a suspension after picking up five bookings in the Segunda Division B, and Catalan told reporters prior to kick-off on Thursday that Levante would lodge an official complaint to the Royal Spanish Football Federation.
The selection of Messi, who did not feature in the first leg, was an indication of Barcelona's intent to progress, and the Argentinian twice came close to scoring in the opening 25 minutes, with goalkeeper Aitor Fernandez parrying away a free-kick before diverting another try wide with his foot.
Yet Barca soon went ahead on aggregate as Dembele benefitted from two moments of good fortune to score twice in as many minutes.
First, the ball looped up off the Frenchman and went in following Erick Cabaco's desperate slide tackle, before Dembele's weak finish from a tight angle was helped in by Fernandez's foot to make it 2-0.
Messi was then played in by Dembele only to see his effort from point-blank range denied by Fernandez, the keeper then thwarting Philippe Coutinho and Messi again before the break.
Barca's aggregate lead was only a solitary goal until Messi finally got on the scoresheet nine minutes into the second half.
Dembele was involved as he threaded a superb pass through to Nelson Semedo, who squared the ball for Messi to slot past Fernandez for the home side's third.
A hat-trick eluded Dembele, though, as he fired just wide late on, while the woodwork denied Emmanuel Boateng scoring for Levante in stoppage time.
What does it mean? Barca through, for now
Levante president Catalan's comments prior to kick-off did not serve as a distraction to Barcelona, who did the job on the pitch. As it stands, they will be in Friday's last-eight draw, though the powers-that-be may have something to say about that.
Dembele at the double
He only scored four times in his debut campaign at Camp Nou but Dembele already has a dozen in 2018-19. There was a degree of luck in both of the 21-year-old's first-half goals, but his link-up play with Messi suggests he is beginning to feel more at home.
Chance to impress passes Coutinho by
Dembele is not the only one to have experienced early struggles in his Barcelona career, with Coutinho as yet failing to hit the same heights he reached at Liverpool prior to his January 2018 move. The Brazilian, who was withdrawn for Luis Suarez just after the hour mark, has still not scored from open play since October.
What's next?
Leaders Barcelona will look to make it seven wins in a row in LaLiga when they host Leganes on Sunday, with Levante hosting Real Valladolid on the same day.
