Vice president Roberto Pescador told Radio Marca (h/t Marca's Angel Rodriguez) the match will be played in their modest 4,000-capacity venue unless they're forced to change locations: "We will play at Las Pistas, unless they force us otherwise. We will not move things around."
Unionistas play in the tiny Estadio Las Pistas del Helmantico, located directly next to the much larger Estadio Helmantico of rivals Salmantino:
Las Pistas has limited facilities and a large running track, seemingly making it ill-suited for modern football. Unionistas do not plan on using the ground for much longer, with plans for a new stadium on the table.
The club was founded in 2013 and has enjoyed a meteoric rise up the Spanish football ladder. But despite their early success, hosting Los Blancos on January 22 will undoubtedly be the biggest match in team history so far. Drawing their formidable opponents meant a lot to the Unionistas players:
Per Gol TV (h/t Marca), one of the players was caught joking with his team-mates during the wild celebrations, saying Real manager Zinedine Zidane "must be s--ting himself right now out of fear."
Unionistas play in the Segunda Division B Group 2, the third tier of Spanish football. They played their first match in 2014, won their first promotion in 2015 and have enjoyed two more promotions since.