A goal from Frenkie de Jong and a Pierre-Emerick Aubameyang hat-trick were enough to give Barcelona an important win over a rather woeful Valencia side.
Xavi's men put the result beyond doubt in the first half with three goals, before Carlos Soler grabbed a consolation and Auba scored a fourth in the second half.
Barcelona were the much better side in the opening exchanges, and were nearly rewarded for their dominance in the 19th minute. After some neat play on the edge of the box, the ball was fed through to Ferran Torres on the right of the penalty area. The new signing's subsequent drilled cross across the six-yard box, however, was just out of the reach of Aubameyang.
Three minutes later Aubameyang got his goal - and it was a beauty. The former Arsenal man latched onto a brilliant long pass from Jordi Alba before rifling the ball emphatically into the top left corner of the net.
The dominance continued thereafter and on the half-hour mark it was 2-0. The goal came following some wonderful play around the box which resulted in Alba (again) lifting the ball over the top of the Valencia defence and into the path of Ousmane Dembele. The French international was then able to cooly slide it across goal to Frenkie de Jong, who made no mistake to bag his third La Liga strike of the season.
Aubameyang was able to make it 3-0 before half-time, with La Blaugrana ripping a completely, utterly, undeniably, hopeless Valencia team apart. The goal was very similar to De Jong's, with a ball being played across the six-yard box and tapped into the net - this time, however, it was Gavi doing the creating and Auba doing the goalscoring.
Valencia finally woke up at the start of the second half, and clawed their way back into the game courtesy of a brilliant headed goal from Soler.
They weren't back in the match for long though, as substitute Pedri came off the bench and immediately cannoned the ball off Auba's back and into the net from about 25-yards out. Pedri was initially awarded the goal, but it was later given to the former Arsenal man.
The home side did create a few chances after that as Barcelona took their foot off the gas, but they just did not have the quality to carve the opposition defence open.
Here's how the Barcelona players rated:
Barcelona player ratings
1. Goalkeeper & defenders
Marc-Andre ter Stegen (GK) - 5/10 - Slapped the ball into his own net in the first half, but got away with it because Gaya was offside. Made amends in the second half with a decent save late on.
Sergino Dest (RB) - 4/10 - Got forward quite well at times but Valencia clearly marked him down as the weak point in defence and they were proved to be right to do this at times.
Ronald Araujo (CB) - 4/10 - Despite Valencia not looking very capable in attack, Araujo wasn't that impressive today. Probably would've had a howler if he had played against anyone, you know, good.
Eric Garcia (CB) - N/A - Subbed off at half-time. He didn't have too much to do in the first half.
Jordi Alba (LB) - 7/10 - Assisted the opener with a great long ball over the top and was great going forward, as he always is.
Frenkie de Jong (CM) - 7/10 - Finally looks back to his best. Bagged the second goal of the game and his overall play was very good until he was subbed off on the hour mark.
Sergio Busquets (CM) - 5/10 - Yeah, just your typical Busquets performance. Passed it around well, can't really run anymore. The usual.
Gavi (CM) - 7/10 - Set up the third. His movement in and out of possession was impressive all afternoon.
Ousmane Dembele (RW) - 6/10 - Set up the second goal and looked livelier (and fitter) than he has in about two years.
Pierre-Emerick Aubameyang (ST) - 8/10 - Bagged a hat-trick. Great performance from Auba, who looks to have finally found some form after a woeful final two seasons at Arsenal.
Ferran Torres (LW) - 6/10 - Decent outing from the Spain international. Caused Valencia's terrible defence problems - particularly during the first half.
Oscar Mingueza - 4/10 - Came on and Valencia scored. Not completely his fault, but also not a good look.
Pedri - 7/10 - 'Assisted' the fourth.
Nico - N/A.
Luuk de Jong - N/A.
Adama Traore - N/A.