Diego Simeone's side sit pretty atop La Liga and the notion that they might run our of steam again during the season has well and truly been put to bed.
Playing home or away has made no difference to his side, and the win over Athletic Bilbao this past weekend showed their class and staying power.
A trip to Camp Nou will certainly hold no fears for his side, and with the second leg at the Vicente Calderon, Atleti may well go into this tie as favourites.
Tata Martino has masterminded a mini revival at Barca. Three wins on the bounce in the league have brought them right back into contention, and they too come into the game with confidence high after taking all three points in the Catalan derby.
It's vital that Barca keep things tight at the back to have any chance over the two legs. An away goal or two could be fatal to their chances of progression, and with Diego Costa leading the line, they are more than capable of registering.
The Blaugrana have kept Costa and his team-mates at bay in the last two games, but the two goalless draws also give an indication of just how difficult the away side will be to breakdown.
However, Atleti have yet to face a fully fit Lionel Messi this season, and the Argentine has played his way back into his best form. A chance to fire Barca in the semi-finals for the seventh successive season will surely be at the forefront of his mind.
Alongside Messi, Neymar has got to up his game because he simply won't get any change from Juanfran if he continues to be so lightweight.
He is the only Barcelona player to score against the Rojiblancos this season and another score from the Brazilian would be very timely indeed.
Pedro Rodriguez simply has to play in this one. Barca look a much better balanced side with the Canary Islander raiding down the channels, and his pace will ensure Filipe Luis is given an uncomfortable night's work.
Left out on Saturday, expect Andres Iniesta to be restored to the line-up alongside Xavi Hernandez and Sergio Busquets.
If Barca can get their passing game going from the off, it can restrict the influence that Koke and Arda Turan will obviously have at some point. There are no two harder working midfielders, and they are players in Simeone's own image, who will work until they drop for their manager.
Simply put, Barca's midfield have to match that work rate, and if they are not prepared to put in a shift, they may as well stay at home.
Who will take the advantage into the second leg?
Costa's threat is obvious and he will be looking to add to his highly impressive seven goals and one assist from five Champions League games, per WhoScored.
With David Villa just returning from injury, Simeone may prefer to keep him in reserve for the second leg, so Raul Garcia may start again.
Javier Mascherano will keep his place alongside Gerard Pique at the heart of Barcelona's defence as will Dani Alves and Jordi Alba on the flanks.
Once the two wing-backs get on the ball, it spreads the play nicely on the Camp Nou surface, whereas Atleti like to keep things compact and central.
Jose Manuel Pinto will of course play the remainder of the season's matches after Victor Valdes' knee injury.