Xavi's side ran out 5-0 winners over Ceuta to make it this far, while the visitors edged a close contest with Mallorca 1-0 in the last 16.
Match preview
Barcelona were given not one, not two, but three scares by Intercity - and more specifically their hat-trick hero Oriol Soldevila - in the last 32 of the Copa del Rey, but the Catalan giants experienced no such heart-in-mouth moments when travelling to third-tier Ceuta.
A brace from Robert Lewandowski complemented strikes from Franck Kessie, Raphinha and Ansu Fati in a five-star performance from the Blaugrana, who are out to win a record-extending 32nd Copa del Rey title and are certainly going about their quest the right way.
However, Xavi admitted that his side's weekend showing left a lot to be desired, where Pedri's first-half goal made the difference in a 1-0 La Liga win over Getafe, but that narrow success keeps the Blaugrana three points clear of Real Madrid at the top of the La Liga standings.
Temporarily turning their attention away from the La Liga title fight, Barcelona are out to qualify for the semi-finals of the Copa del Rey for the 11th time in 13 seasons, and they enter Wednesday's all-La Liga clash with a six-game winning run in all tournaments to protect.
Ten of Barcelona's last 11 games have ended in victory - with the outlier being their 1-1 draw with Espanyol on New Year's Eve - but Sociedad will pose the biggest threat to their hopes of Copa del Rey glory yet.
Barcelona know a thing or two about winning football matches, but Real Sociedad have developed quite the knack for victories themselves, edging out the Blaugrana's green streak by one as they arrive in Catalonia aiming to secure an eighth successive victory in all competitions.
Imanol Alguacil's side struck within the first five minutes of their Copa del Rey last-16 clash with Mallorca through Robert Navarro, and that was enough to send the White and Blues through to the quarter-finals for the second successive year.
Sociedad followed up that narrow success with a comfortable 2-0 La Liga win over Rayo Vallecano on Saturday, where Alexander Sorloth and Ander Barrenetxea both made the net ripple in the first 45 minutes to cement their position in third place in the table - three points behind Real Madrid and six adrift of Barcelona having played a game more.
While Sociedad's victories have come against teams that they would have expected to beat, take nothing away from the defensive excellence on show, as Alguacil's men have conceded just one goal in their last 630 minutes of football and are out to right the wrongs of 2021-22, where their Copa del Rey quarter-final ended in a 4-0 humiliation at the hands of Real Betis.
However, Barcelona breached Sociedad's rearguard at will in a 4-1 romping of the visitors back in August - their seventh successive win over the White and Blues in all tournaments - and Sociedad have failed to win in 16 against the Blaugrana since Mikel Oyarzabal struck in a 1-0 victory in April 2016.
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Team News
Barcelona boss Xavi will welcome Robert Lewandowski and Ferran Torres back to his squad amid the pair's La Liga suspensions, but Andreas Christensen had to come off at half time in Sunday's win over Getafe with hamstring discomfort.
Christensen is not believed to be nursing anything serious and was able to complete Monday's recovery session, but Ronald Araujo should expect a recall to the backline in any case, and Xavi has no other injury concerns to work around for the quarter-final.
While a plethora of second-string players earned chances to impress against Ceuta, Xavi should name a more recognisable XI given the calibre of opposition, with Lewandowski set to take the place of Fati at the tip of the attack.
As for Real Sociedad, a lengthy injury list still includes Alex Sola, Mikel Merino, Ander Guevara, Andoni Gorosabel, Jon Pacheco, Sadiq Umar, Martín Merquelanz and Mohamed-Ali Cho, with Merino and Gorosabel both coming off with problems in the last-16 win over Mallorca.
The in-demand Merino is supposedly set for a month out with his hamstring injury, but Alguacil still has a couple of options for change in the final third, as Oyarzabal builds up his fitness following his devastating cruciate ligament rupture.
Takefusa Kubo did not see the field against Rayo Vallecano as a precaution, but the Japan international trained normally on Monday and should also be in contention for a starting role here alongside Barcelona-linked Martin Zubimendi, who returns from suspension to tackle his admirers.
Barcelona possible starting lineup:
Ter Stegen; Kounde, Araujo, Garcia, Alba; Pedri, Busquets, De Jong; Dembele, Lewandowski, Raphinha
Real Sociedad possible starting lineup:
Remiro; Elustondo, Zubeldia, Le Normand, Rico; Mendez, Illarramendi, Zubimendi; Silva; Sorloth, Oyarzabal
We say: Barcelona 1-0 Real Sociedad
Sociedad's penchant for victories amid their injury crisis has been admirable, and having seen Getafe operate a low block to good effect against Barcelona, Alguacil's defensively-sound side can feel confident of keeping the Blaugrana at bay for large portions of the game.