Pione Sisto had equalised for Celta after Jose Arnaiz found the net for Barca in the first leg at Estadio de Balaidos; an away-goal that gives Barca a small advantage, although their manager, Ernesto Valverde, won't try to sit back and defend that narrow advantage.
On Wednesday, Real Madrid laboured to a 2-2 draw with Numancia to progress to the quarter-finals 5-2 on aggregate.More news: All Mac, iOS devices affected by chip bugs but safe now: Apple
#5 Celta Vigo lost the plot in the first halfCelta defence had no answers for Messi & Co.
Barcelona will be in better shape having rested their key men in the first leg, while the Sky Blues could play a third game in a week with their strongest squad.
With Celta Vigo in such good form and looking to go three games unbeaten against Barcelona, Real Madrid and Barcelona again, this is one you don't want to miss.More news: GOP lawmaker proposes bill to grant residency for Salvadoran immigrants
Not long after, Andres Iniesta was also withdrawn from the action, and given there was no need to chase more goals, Barcelona were happy to hold the ball and conserve energy for much of the second period.
The speed of Barcelona's attack caught the visitors off guard, especially Sergi Gomez and Fontas.
The France worldwide has not played since suffering the problem in a 2-2 home draw against Celta Vigo on December 2. They were all over the place at the back, allowing Barcelona to break them on a consistent basis.
Wissam Ben Yedder, after 31 minutes, and Joaquin Correa in the 54th minute, were on target for Vincenzo Montella's team.More news: Toyota is the latest auto maker to add Alexa to its cars
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