The move away from Camp Nou for the first time in 65 years has had little effect on Barcelona, who came into this game having recorded consecutive 5-0 wins at adopted ground Estadi Olímpic Lluis Companys.
The evening sun welcomed a capacity 45,000-strong crowd to see their side dominate the opening exchanges, but they struggled to turn their possession into attempts on Iván Villar’s goal.
Buoyed by last season’s final day win against Barça which preserved their La Liga status, Celta used their little time on the ball to forge the first chance. Iago Aspas’ attempted lob was tipped over by Marc-Andre ter Stegen, but the Galicians went one better from the resulting corner.
A poor clearance from the home side allowed Luca de la Torre to poke through to Jorgen Strand Larsen, who this time gave Ter Stegen no chance, placing into the far corner.
The surprise goal did little to change Barça’s approach, and openings in the staunch Celta defence remained few and far between. In fact, the only other clear opportunity of the first half went the way of the visitors, as Larsen’s header was saved well by Ter Stegen and De la Torre fired over on the rebound.
In an attempt to make amends for a substandard opening period, a change of shape for Barcelona was accompanied by the introduction of teenage sensation Lamine Yamal.
Celta nevertheless continued to enjoy the majority of the openings, and there was soon a deserved second.
A blistering counter saw Aspas thread through Tasos Douvikas, and the Greek substitute finished emphatically one-on-one with his first touch of the game.
Ultimately, dominance for 80 minutes is often not enough when playing a side of Barcelona’s quality. Nerves in the Celta camp were unsettled when Joao Felix superbly lifted the ball over the top to Robert Lewandowski, and the legendary striker lobbed Villar with style.
The quick-fire equaliser came just minutes later when Cancelo pulled back for Lewandowski to smash in from the centre of the box, and the comeback was to be completed within a scintillating final 10 minutes.
Gavi lobbed a pass over the entire Celta defence, where Cancelo steamed in to prod past Villar and crown a famous comeback in Catalonia.