Athletic Club are 23-times winners of this competition, most recently triumphing in 1984.
More recently, Athletic have fallen at the final hurdle in 2009, 2012, 2015, 2020 and 2021, so will this finally be their year?
In this season’s competition so far, Ernesto Valverde’s team have seen off Alzira 2-0 and then Sestao River Club 1-0.
Meantime, in La Liga, the Lions find themselves fifth, just two points outside the Champions League spots, following a goalless draw with Real Betis last Thursday.
So, Athletic Club make the long trip to Elda as overwhelming favourites to advance.
Hosts Eldense are from Spain’s third-tier, Primera Federación, and are competing at this stage for the first time since 1987.
Back then, they got all the way to the round of 16, falling to Mallorca Atlético, back before B teams were banned.
This time round, having already dumped out Coruxo and then Burgos, Eldense are rewarded with this glamour tie.
Will Athletic Club be far too strong at Estadio Municipal Nuevo Pepico Amat?