Real Sociedad have not beaten Atletico Madrid in La Liga since 2019, but they did win the most recent meeting.
April's Copa del Rey final was an epic 2-2 draw, before a tense 30 minutes of extra time and a heroic goalkeeping performance from Unai Marrero, who saved twice in the penalty shootout to help the Basque club lift the trophy.
Marrero started his team's most recent game, last Monday's 3-2 win at Elche, extending their unbeaten run to three matches. They lost 1-0 to Real Betis and 4-1 at Real Madrid in the opening rounds but beat Espanyol 2-1 and then drew 0-0 with Real Sociedad.
They host Bournemouth in the Europa League on Thursday, but before that they take on Atletico, who lost 3-0 along the coast in Bilbao last Saturday and were beaten 2-1 at Liverpool in the UEFA Champions League.
Those results came after picking up seven points from their first three La Liga games but there is a feeling that Diego Simeone is still searching for his best combinations, and his side could come unstuck in San Sebastian.
Best Bet - Real Sociedad to win and both teams to score @ 9/2
Alternative Bet - Mikel Oyarzabal anytime goalscorer @ 6/4
Bet Builder - HT: Draw - FT: Real Sociedad, Job Ochieng to score or assist & Alex Baena to score @ 85/1
Best Bet - Real Sociedad to win and both teams to score @ 9/2
This is a proper chance for La Real to break their Atleti hoodoo.
Los Colchoneros are still easing themselves into the season after a summer dominated by the saga that became Julian Alvarez's failed move to Barcelona.
Diego Simeone seems uncertain how to set up his team, and while there were good spells in the defeats at San Mames and Anfield, the former was typical of his team's lacklustre start.
After going into the break drawing 0-0, Atleti were 2-0 down by 48 minutes, effectively conceding twice from their own kick-offs and after Tuesday, have now lost five of their last 10 competitive games.
Sociedad deservedly won April's Copa final, and that result may have been enough to persuade Pellegrino Matarazzo's team that they can finally beat Atletico in La Liga.
Add in that both teams have scored in 14 of Sociedad's last 17 La Liga home games, and Sunday's match could produce a big-price winner.
Alternative Bet - Mikel Oyarzabal anytime goalscorer @ 6/4
A World Cup winner and European champion, Mikel Oyarzabal scored a penalty in that Copa del Rey final and is Sociedad's talisman.
He has had a lightly tweaked, withdrawn role this season, either playing behind Orri Oskarsson or leading the line alongside another creative player like he did with Luka Sucic at Elche.
Oyarzabal has provided two assists but still hasn't scored this season. However, before his cup final effort, he netted at the Metropolitano in the league and can hurt Atleti again.
HT: Draw - FT: Real Sociedad
Job Ochieng to score or assist
Alex Baena to score
Pays 85/1
Four of Sociedad's five games this season have been level at half-time, and another draw after 45 minutes, before the hosts go on to win appeals.
So does a goal involvement for home midfielder Job Ochieng, who scored a goal and registered two assists at Elche, becoming the first Sociedad player to record three goal involvements in a single game.
Ochieng can continue his form on Sunday, as can Atletico's Alex Baena.
Another Spanish World Cup winner who hasn't played in his usual position this season, Baena featured wide on the left for La Roja this summer but has played up front this season and scored three times.
With Alvarez still not fully firing, Baena can lead Atleti again and contribute a goal to ensure both teams score for the fourth head-to-head in a row.
Real Sociedad have not beaten Atletico Madrid in La Liga since 2019
La Real have taken seven points from the last nine available
Atletico Madrid have lost their last two games
Job Ochiang became the first Sociedad player to provide three goal involvements in a single game in the 3-2 win at Elche
Alex Baena has scored three goals this season
Both teams have scored in 14 of Sociedad's last 17 La Liga home games
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This article was written by a partner sports writer via Spotlight Sports Group. All odds displayed on this page were correct at the time of writing and are subject to withdrawal or change at any time.