Liverpool fans will never forget their 4-0 win over Barcelona in 2019.The Reds have enjoyed some truly remarkable Champions League nights at Anfield over the years, but nothing will ever compare to the celebrations when they completed the mother of all comebacks.Having been on the receiving end of a 3-0 pasting at Camp Nou courtesy of Lionel Messi's brace and a strike from Luis Suarez, Liverpool looked to be on the brink of a crushing semi-final exit.

Liverpool 4-0 Barcelona

However, despite the absence of Mohamed Salah and Roberto Firmino, Liverpool managed to fight back in stunning fashion with Divock Origi getting the party started after just seven minutes.

Georginio Wijnaldum then levelled the aggregate scores with a breath-taking brace early in the second-half, before Trent Alexander-Arnold's iconic quick corner set up Origi to score the winner.

It gives you goosebumps thinking about it, doesn't it? And things were made all the more perfect for Liverpool fans due to the fact that Barcelona's side of the story was captured in a documentary.

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Barcelona's behind-the-scenes documentary

If ever you've seen clips of Jordi Alba filling up with tears in the Anfield dressing room or Messi trying to rally the troops, then you've seen part of Rakuten's nine-part programme on Barcelona in 2019.

'Matchday: Inside FC Barcelona,' captured some of the Barca squad's most intimate moments during the crushing loss in its penultimate episode - and even included an appearance from Shakira.

No, she wasn't performing a rendition of 'Waka Waka (This Time for Africa)' but rather, cheering on her husband, Gerard Pique, along with her two sons from the comfort of their home.

Shakira's heartbroken reaction

It was fascinating to watch the perspective of one of the Barcelona players' spouse during such a devastating game and you can see just how much the Catalans' capitulation meant to the singer.

And that was especially the case during viral footage, which was included in the documentary trailer, where Shakira reacts to Wijnaldum levelling the aggregate scores at 3-3 with a superb header.

Having newly witnessed Wijnaldum rocking the boat with his first of the night, one of Shakira's sons tries to comfort here by saying: "If it stays like this, it doesn't matter. We'll go through to the final."

Famous last words, I'm afraid, because Liverpool found the back of the net just 122 seconds later with Sharkia declaring: "No! I can't believe it!" as Wijnaldum doubled his money in brilliant style.

Barcelona still reeling from defeat

The footage of Pique's spouse looking so gutted is yet another reminder of just how heartbreaking the Liverpool comeback proved to be for Barcelona, particularly after the AS Roma collapse, too.

It really does feel as though the Camp Nou-based club never really recovered from the traumatising loss and that it ultimately set the wheels in motion for the rapid decline that we've seen ever since.

Fast-forward though an 8-2 defeat to Bayern Munich and Messi leaving the club and you find Barca in a very different place to the side that was on the brink of reaching the Champions League final.

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