Villarreal sit five points clear of seventh-placed Athletic Bilbao in the La Liga table, while Real Sociedad are three points ahead of fifth-placed Real Betis in the battle to secure a Champions League finish.
Match preview
Villarreal suffered disappointment in the Europa Conference League earlier this month, losing 2-1 on aggregate to Anderlecht in the round of 16, but they are in strong form in La Liga, picking up 10 points from their last four matches against Getafe, Almeria, Real Betis and Osasuna.
The Yellow Submarine were 3-0 winners over Osasuna in the league last time out, with the result leaving them in sixth position in the table, five points ahead of seventh-placed Athletic.
Villarreal are only seven points behind fourth-placed Real Sociedad, meanwhile, so a victory in this match would put them right back in the picture for a possible Champions League spot.
Quique Setien's side have not lost in the league since the middle of February, while they have been in strong form at home this season, picking up 23 points from 12 matches.
Real Sociedad, though, have the fourth-beat away record in the division this term, securing 26 points from 13 matches, recording eight wins in the process.
Villarreal have only actually won one of their last six La Liga games against Real Sociedad, meanwhile, and they suffered a 1-0 loss in the reverse match earlier this season.
The visitors will enter this match off the back of a 2-0 victory over Elche, with Takefusa Kubo and Ander Barrenetxea on the scoresheet in San Sebastian, as the Basque side secured a vital win.
Real Sociedad had actually gone four league matches without a win before their triumph over Elche, which moved them onto 48 points, leaving them in fourth position in the table, three points ahead of fifth-placed Real Betis in the battle for a Champions League finish.
Imanol Alguacil's side were knocked out of the Europa League by Roma earlier this month, so their full focus is on claiming a top-four finish, which would represent an excellent campaign.
The White and Blues have not finished fourth in La Liga for 10 years, and April could be a decisive month, as they prepare to take on Villarreal, Getafe, Athletic, Rayo Vallecano, Real Betis and Osasuna.
Real Sociedad are unbeaten at the home of Villarreal since January 2018, and they will be bidding to make it three straight league wins over the Yellow Submarine in Sunday's mouthwatering affair.
Villarreal La Liga form:
L
L
W
W
D
W
Villarreal form (all competitions):
W
W
D
D
L
W
Real Sociedad La Liga form:
W
D
L
D
D
W
Real Sociedad form (all competitions):
L
D
L
D
D
W
Team News
Villarreal will be missing Etienne Capoue, Francis Coquelin and Gerard Moreno through injury for Sunday's affair, but Alex Baena is available again following a suspension.
Jose Luis Morales scored twice off the bench against Osasuna last time out, and the Spaniard should come in to lead the home side's attack here in the absence of Gerard Moreno.
Giovani Lo Celso is also pushing for a start, but it is expected to be largely the same side that took to the field for the first whistle in the team's last match before the international break.
As for Real Sociedad, Umar Sadiq, Martin Merquelanz and Aritz Elustondo will miss the match through injury, but Carlos Fernandez and Mikel Merino are both back after serving bans last time out.
Merino should come back into the midfield for the visitors, but Fernandez could remain on the bench, with Kubo potentially retaining his spot alongside Alexander Sorloth.
Mikel Oyarzabal was only a substitute against Elche, but the Spaniard is expected to come back into the starting side for the clash with the Yellow Submarine.
Villarreal possible starting lineup:
Reina; Foyth, Albiol, P Torres, Pedraza; Baena, Parejo, Trigueros; Chukwueze, Morales, Pino
Real Sociedad possible starting lineup:
Remiro; Barrenetxea, Zubeldia, Le Normand, Rico; Mendez, Zubimendi, Merino; Kubo, Sorloth, Oyarzabal
We say: Villarreal 1-1 Real Sociedad
There is no downplaying the importance of this match to both teams, and it should be an entertaining match on Sunday evening. Villarreal are the form team entering this game, but Real Sociedad have enough quality to secure a share of the spoils this weekend.