The home side will enter the contest off the back of a 1-0 defeat to Valencia, while Cadiz boosted their survival hopes with a 1-0 victory over Rayo Vallecano last time out.
Match preview
Not too long ago, Real Sociedad were comfortable in the top four and chasing down second-placed Real Madrid in the table but that is no longer the case due to a patchy run of form.
Indeed, the Basque outfit have won just one of their last five league games, suffering two defeats in the process, including a 1-0 reverse to Valencia last time out.
The loss at Mestalla left them on 43 points from 23 matches, which is still enough to sit third, but they are only one point clear of fourth-placed Atletico Madrid and just three clear of Real Betis in fifth.
Imanol Alguacil's side have only collected one point from their last two games in front of their own supporters, meanwhile, losing against Real Valladolid before being held to a 1-1 draw by Celta Vigo.
The White and Blues have not claimed a top-four spot in La Liga since 2013, so it would be a huge achievement to finish in the Champions League positions, while they are still in the Europa League, preparing to tae on Roma in the last-16 stage of the competition.
Cadiz, meanwhile, will enter this match off the back of a 1-0 win over Rayo Vallecano, with Sergi Guardiola netting the only goal of the contest in the 74th minute.
The Yellow Submarine have now been victorious in each of their last three league games in front of their own supporters, while they are unbeaten in La Liga at home since September 10, which is an excellent record considering their position in the table.
Unsurprisingly, Cadiz's away form this season has been disappointing, only managing eight points from 11 matches, but they will be travelling to a Real Sociedad side that have dropped points in six of their 11 games in front of their own fans this term.
Sergio Gonzalez's side are currently 16th in the table, two points clear of 18th-placed Valencia, so they are still very much in a relegation battle despite winning three of their last five league games.
Cadiz have lost each of their last five La Liga matches against Real Sociedad, meanwhile, including a 1-0 defeat in the reverse game earlier this season.
Real Sociedad La Liga form:
W
D
L
W
D
L
Real Sociedad form (all competitions):
L
D
L
W
D
L
Cadiz La Liga form:
L
W
L
W
L
W
Team News
Real Sociedad still have a number of injury problems, with Aritz Elustondo, David Silva, Mohamed Ali-Cho, Sadiq Umar and Martin Merquelanz ruled out of Friday night's contest.
Head coach Alguacil is expected to resist the temptation to shuffle his pack following the 1-0 loss at Valencia, although there could be a change at right-back, with Alex Sola potentially coming into the side.
Mikel Oyarzabal and Takefusa Kubo should again support Alexander Sorloth in the final third of the field, while Mikel Merino is expected to again feature in central midfield.
As for Cadiz, Brian Ocampo, Alvaro Negredo, Jose Mari, Juan Cala, Jon Ander Garrido and Joseba Zaldua have been ruled out of the match through injury.
The visitors do not have any fresh concerns from their victory over Rayo last time out, though, so it would not be a surprise to see the same XI take to the field.
Guardiola should again be joined by Roger in the front two despite pressure from Anthony Lozano, while Ruben Alcaraz is likely to hold off competition from Fede San Emeterio to start in central midfield.
Real Sociedad possible starting lineup:
Remiro; Sola, Zubeldia, Le Normand, Rico; Mendez, Zubimendi, Merino; Kubo, Sorloth, Oyarzabal
Cadiz possible starting lineup:
Ledesma; Carcelen, Hernandez, Fali, Espino; Bongonda, Escalante, Alcaraz, Sobrino; Guardiola, Roger
We say: Real Sociedad 2-1 Cadiz
Real Sociedad desperately need to return to winning ways as they battle to stay in the top four, and we are expecting the hosts to triumph on Friday evening. Cadiz's home form in recent months has been excellent, but they are a different team on the road, and Real Sociedad should secure all three points here.