Ernesto Valverde's side suffered a blip in midweek as Barcelona were held to a 1-1 draw away to relegation-threatened Las Palmas, while Atletico Madrid cut their lead at the top to five points following their 4-0 win against Leganes on Wednesday.
Diego Simeone knows the importance of a win at the Nou Camp on Sunday, which could set up an intriguing game when these two sides face each other.
Here's everything you need to know ahead of the game on Sunday.
Atletico Madrid's last trip to the Nou Camp in February 2017, although ultimately an unsuccessful one, didn't fall short in terms of entertainment.
After suffering a 2-1 defeat in the Copa del Rey semi-final first leg at home, the second leg had everything from goals, red cards and a missed penalty as Barcelona managed to book their place in the final.
A first half Luis Suarez goal but the hosts on the cusp of winning the tie, before Sergi Roberto and Yannick Carassco both saw red for two yellow cards.
It wasn't Atletico's night, as Antoine Griezmann had a goal incorrectly ruled out for offside, Kevin Gameiro missed a penalty before his goal seven minutes from time set up an entertaining finish to a fascinating cup tie.
There was even time for Suarez to see red himself in the dying embers of the game, although Barcelona had enough to see the game through and their passage into the final.
Samuel Umtiti vs Antoine Griezmann
Although teammates for the national team, Samuel Umtiti will have to put that to one side for the game on Sunday if he is to stop an in-form Antoine Griezmann.
The former Real Sociedad man enjoying a purple patch in recent outings, scoring seven goals in his last two La Liga games. Undoubtedly the key man for Simeone's side, Umtiti will have to be on top form to deny Griezmann come Sunday.
A forward who likes to drift off the front line and play slightly deeper, Umtiti will have to deny his compatriot any space to turn and run at him. Able to finish with either foot or head as well, the former Lyon man will need to be aware of his late runs into the penalty area and deny Griezmann with time that could seriously punish Barcelona.
Velverde has no fresh injuries following the games against Las Palmas on Thursday. He will be without Nelson Semedo (hamstring) and Sergi Samper (ankle ligaments) for the game on Sunday in what are his only absentees.
Simeone meanwhile only has one injury of his own to contend with. The Argentine will be missing Lucas Hernandez (hamstring) for Sunday.
Potential Barcelona Starting Lineup: ter Stegan; Roberto, Pique, Umtiti, Alba; Busquets, Iniesta, Paulinho; Messi, Suarez, Coutinho
Potential Atletico Madrid Starting Lineup: Oblak; Juanfran, Gimenez, Godin, Filipe Luis; Koke, Thomas, Saul, Correra; Costa, Griezmann
Both sides know the importance of a win on Sunday as two of La Liga's biggest sides go head-to-head.
A win for Barcelona will see their lead stretch to eight points, while a win for Atletico see them come within two points of their hosts and end their unbeaten record in La Liga in the process.
In such an important game however, both sides will be desperate not to lose the game, which could ultimately decide the fate of what is set up to be a tactically enthralling encounter.
Prediction: Barcelona 1-1 Atletico Madrid