Liverpool's utterly breathtaking 4-0 win over Barcelona in the Champions League semi-final will live long in the memory for many, and fans of the Blaugrana will struggle to shake the image of their side being comprehensively dismantled.
This was the La Liga champions, the perennial European contenders, the team with Lionel Messi, and they simply had no answer for what Liverpool did to them. It begs the question - why?
The thing that is most concerning for Barcelona fans is not that this event happened, but that this isn't even the first time.
Think back to last season's quarter-final, when Barcelona picked up a 4-1 win over Roma at Camp Nou in the first leg. Their semi-final spot looked a certainty, but the Serie A side fought back to a 3-0 win in the second leg and left Ernesto Valverde's men licking their wounds.
There is a mentality problem in this team, and it all seems to come back to the manager. With Pep Guardiola or Luis Enrique at the helm, Barcelona become a possession-heavy juggernaut who could not be stopped. But, with Valverde leading the side, that identity has disappeared.
During his two years at the club, it seems as though he is yet to figure out the style of play he wants to adopt. Instead, he relies on the sheer talent of the squad to carry him through. With the likes of Messi, Luis Suarez and Gerard Pique in the team, that has often been enough to achieve success, but not in the Champions League.
When relying on ability does not work, as it did not against Roma or Liverpool, Barcelona simply don't know what to do. Valverde has not told them what to do, and they have no system to try and fight their way back into contention.
Fans online will often say "even I could win the Champions League with this team", but it's not that easy.
The problem for Valverde is that Barcelona are a club who demands dominance, not just excellence. Winning La Liga and potentially adding the Copa del Rey is not a big deal for the Blaugrana, they need to win the Champions League. Not only are they not doing that, but they're becoming a laughing stock.
When a well-oiled machine like Liverpool come up against a hapless bunch of confused stars, there is only going to be one winner, and Barcelona have to realise that now.
Valverde faced criticism last season, but has not learned from his mistakes. This time, it could prove to be the final straw for Barcelona chiefs. They need someone like Ajax's Erik ten Hag to come in and restore their identity because, under Valverde, they will not achieve either.
Players have to take a share of the blame for underperforming, but Valverde's influence - or should I say lack thereof - is clear to see. He offers nothing to this side, and it's time for change.