A comeback like the one against Paris Saint-Germain in 2017 was needed, and whilst unlikely, Barca could rely on the fact that they'd won every home match in 2025/26, and in the calendar year alone, had won all five games by a three-goal margin.
Lightning-fast start from Barca
If Atleti were still going to triumph and make their first final since the epic win over Real Madrid at the Santiago Bernabeu in 2013, they were going to have to work for it.
As might be expected, the hosts came roaring out of the blocks and had two chances in the opening two minutes.
Three more in the opening quarter hour and 71% collective possession saw to it that the visitors rarely left their own half.
Certainly, Julian Alvarez was like a little boy lost up front for Atleti, and had barely touched the ball in a frenetic period.
Sensational display from Lamine
All of Barca's big names were at it from the first whistle, with Lamine Yamal unusually physical in a sensational all-round display.
23 total duels engaged in with 14 won by the end of proceedings were unbeatable, without taking into account his 18 dribbles, 11 touches in the opposition box and 104 total touches - one of five Barca players to have a century or more on the night.
Despite such incredible dominance, the Catalans were always likely to fear a ball in behind, given that their defensive line was often stationed inside Atleti's half, stifling the Rojiblancos' creativity.
Antoine Griezmann's shot on target - Atleti's first - on 27 minutes, was enough to silence the Camp Nou, and evidenced how much of a knife-edge the game was on.
Bernal calms the nerves
The fear was soon calmed by Marc Bernal's simple finish from a Lamine cross two minutes later, however.
Atleti had failed to win any of their last nine games when conceding first in the Copa del Rey, since their victory over Reus Deportiu on 1st December 2015, and Barca had won three games in the competition this year when scoring the opening goal, so it already appeared to be a question of whether Flick's men could get the goals they needed to progress.
They certainly continued to dominate the ball with a number of players posting pass completion stats of well over 90%.
Ademola Lookman's missed opportunity during stoppage time was immediately punished as Pedri was fouled by Marc Pubill in the area, and Raphinha stroked home the resulting penalty with the last kick of the first half.
Two down, two to go.
Atleti come back out fighting
If Atleti's more positive outlook from the beginning of the second half was meant to see Barca in retreat, it had quite the opposite effect.
After Alvarez's 48th-minute attempt, the hosts fired back with three more of their own, with the corner count rising with almost every attack too.
Three of Barca's four defenders - Pau Cubarsi, Gerard Martin and Joao Cancelo - hit double figures for their final third entries (23, 21 and 13 respectively), finding their targets with relative ease, and with man-of-the-match Pedri also doing similarly well (26 FTE), there simply was no way out for Atleti.
Diego Simeone reacted by making a double substitution just before the hour, which had the briefest of effects as Alexander Sorloth came off the bench and saw an immediate chance blocked, whilst fellow sub Nahuel Molina's shot was off target.
Three down, one to go
From Barca's 10th corner of the game, the ball came back to Cancelo, who picked out Bernal to volley home a third with 20 minutes still to play.
Given that the hosts were still collectively keeping the ball for 71% of the time, it was going to be the longest 20 minutes that the Rojiblancos had played in a while.
Four more chances came and went for the Catalans, who just came up short in the end, with Simeone undoubtedly indebted to his entire team's defensive effort, but to Marcos Llorente in particular.
The Spaniard's 100% record for tackles made during the game, and his athleticism to consistently snuff out a Barca attack, can be said to be a major reason why Hansi Flick's side couldn't get over the line.
Atleti's night but Barca can be proud
When your keeper - Juan Musso - also pulls off six saves, you know that it's likely to be your night.
Barca can at least hold their heads high in defeat and bow out of the competition that they won last year.
When they look back at the match to see that they'd won every single facet of the game fairly comprehensively, there really was little more that they could've done, even if that remains scant consolation.
Catch up on the match with Flashscore.
