Jose Luis Mendilibar's Eibar will certainly fancy themselves going into this tie, although it might be wise to be wary of Navalcarnero, who made a name for themselves in the second round when they beat Las Palmas 1-0.
Navalcarnero, a side who have spent the majority of their 60-year existence competing in the lower reaches of the Spanish football league system, will have a rare opportunity to face off against La Liga opposition on Sunday.
Not exactly famed for their attacking prowess, eyebrows were raised when Las Coloncheras found a way past Las Palmas last time out, knocking out the Segunda Division side.
It is worth stating that it was far from a dominant performance by the Castilian minnows, with Andres Sanz's team only nicking the win in added time, courtesy of a goal from Wandy Guerreiro Ribeiro Dos Santos.
Still, Sanz's men find themselves in the round of 32, with a unique opportunity to force their way into the latter stages of the competition.
Eibar, who currently sit 15th in La Liga, just three points off the drop zone, have seen their promising start to the campaign fall flat in recent weeks.
After Bryan Gil's sensational brace against Granada provided Mendilibar's men with their first win of the new year, Los Armeros were undone against Levante following a late comeback at the Estadi Ciutat de Valencia.
In the Copa del Rey, Eibar have been promising so far, but like so many other La Liga sides this season, they have been forced to weather scares against lower-league opposition.
In the second round, their tie with Las Rozas went all the way to extra-time after the original 90 minutes ended 3-3. In the end, Sergi Enrich was the man of the hour for Los Armeros, netting his side's fourth of the game in the 108th minute.
Navalcarnero Copa del Rey form: WW
Navalcarnero form (all competitions): WDDDWW
Eibar Copa del Rey form: WW
Eibar form (all competitions): LLDWWL
Mendilibar is likely to rest a number of his key players in this tie, confident that he has enough talent in his squad to see off Navalcarnero.
Regardless of squad rotation, Los Armeros will be without Roberto Correa and Jose Angel who are both currently injured. Gil did not take part in his side's loss to Levante and could be rested again on Sunday.
Kike Garcia extended his contract with Eibar on Wednesday in a move that will see the veteran attacker remain at the club until at least 2023. Mendilibar could call upon the striker in this tie.
As for Navalcarnero, the hosts have not played a league game since mid-December, meaning that Sanz will be able to call upon a fresh squad for this tie.
Navalcarnero possible starting lineup:
Nestor; Ruiz, Nieto, Calvo, Otero; Monteagudo, Poblador, Alvarez, Soria; Ramirez, Esnaider
Eibar possible starting lineup:
Yoel; Cubero, Burgos, Arbilla, Rodrigues; Leon, Alvarez, Quique, Recio, Kadzior; Muto
We say: Navalcarnero 0-2 Eibar
Navalcarnero were fortunate in their win over Las Palmas. We think that, against Eibar, the hosts will have their work cut out for them. Eibar are a far superior side and could put a couple past Sanz's men.