The Blanquivioletas may have their relegation confirmed, but they were keen to impress against Hansi Flick’s rotated side.
Ivan Sanchez epitomised that as he stood up Ronald Araujo and got a shot off, and he got some luck as it bounced off the defender and awkwardly spun past Marc-Andre ter Stegen just six minutes into the goalkeeper’s return from injury.
Raúl Moro then forced a save from the goalkeeper, while Pau Víctor called André Ferreira into action either side of that attempt. Ansu Fati and Fermín López both saw a shot blocked as Valladolid valiantly held onto their lead.
Despite his side being behind, Barcelona debutant Dani Rodríguez had bright moments and jinked inside before sending a shot wide.
Fati then cut in from the opposite wing and let off a strike that was eye-catchingly palmed away by Ferreira on the half-hour mark.
Rodriguez’s evening came to an unfortunate end shortly after as he was forced off by a shoulder injury, and the frustration continued for his teammates still on the pitch even after Lamine Yamal’s introduction and their domination of possession.
Raphinha and Frenkie de Jong were introduced at half-time, and having shown intent from the moment he came on, the former controlled Ferreira’s attempted punch and fired into the bottom corner.
Barca had to wait just seven more minutes to take the lead, as Gerard Martin picked out Fermin for the midfielder to provide a clinical first-time finish.
While the visitors pushed forward again, with Héctor Fort hitting the post following some dazzling footwork, Juanmi Latasa worked Ter Stegen with attempts either side of that effort.
There was concern for Gavi when he went off, and Antonio Candela miraculously cleared Yamal’s shot off the line, but there was no stopping Barcelona from recording their fourth consecutive victory in LaLiga.
That ensured they will be at least four points ahead of Real Madrid when the two title rivals and bitter foes meet in El Clásico next week. In contrast, Valladolid suffered an eighth consecutive top-flight defeat for the first time in their history.