Liverpool fans will never forget their 4-0 victory over Barcelona at Anfield.

In May 2019, Jurgen Klopp's side pulled off the impossible, bouncing back from a 3-0 first leg defeat to reach the Champions League final.

They also achieved that feat without both Mohamed Salah and Roberto Firmino, with their replacements Xherdan Shaqiri and Divock Origi shining on the night - the latter scoring a famous brace.

There wasn't one Barcelona player who performed close to their best at Anfield, but the game was a particularly bad one for Jordi Alba.

The left-back made mistakes in the build-up to Liverpool's first two goals and was woeful throughout the entirety of the match.

Wijnaldum celebrates

Alba just wasn't his usual self and that became even more apparent after Barcelona released footage of the players in the dressing room at half-time as part of their eight-episode 'Matchday' series.

Despite the score only being 1-0 to Liverpool, Alba looked absolutely distraught in the middle of Ernesto Valverde's message to his team.

The left-back had his head buried in a towel and was being comforted by a Barcelona staff member.

Alba was then asked if he was okay, to which he replied to Valverde: "Go on, go on."

Video

The behind-the-scenes footage is still remarkable to watch and you have to wonder why Alba was allowed to continue.

Clearly, something wasn't right and eight minutes into the second half, the Spaniard surrendered possession to Trent Alexander-Arnold, who then assisted Gini Wijnaldum to make it 2-0 to Liverpool.

What happened after that is the stuff of legend.

Half-time substitute Wijnaldum netted his second goal of the game in the 56th-minute with a thumping header, levelling the scores on aggregate.

Then with just 11 minutes remaining of normal time, Alexander-Arnold and Origi combined for one of the Champions League's most iconic strikes.

Origi's goal

The right-back's quickly-taken corner found Origi unmarked in the box and the Belgian striker fired the ball into the net, sparking scenes of pandemonium at Anfield.

Maybe Alba knew what was coming at half-time...