Last season, Rayo Vallecano reached the semi-finals of this competition for the first time ever, targeting a similarly lengthy run this year too.
In round one, los Franjirrojos easily saw off sixth-tier Mollerussa 3-1, with Bebé, Diego Méndez and Sergio Camello on target.
Meantime, in La Liga, los Vallecanos are currently eighth, having finished 12th as a newly-promoted club last time round.
So, Andoni Iraola’s team should cruise through to round three.
Hosts Atlético Saguntino meanwhile ply their trade in the Segunda Federación, part of Spain’s fourth-tier.
Last month, they won a Copa del Rey tie for the first time ever, ousting third division Amorebieta 1-0, thanks to Juanma Acevedo’s penalty deep into extra time.
So, this’ll be a massive occasion at Estadio Nou Camp de Morvedre, with Rayo likely to be simply too strong.