Graham Hunter Apr 28, 2026, 05:00 AM ET Close Graham Hunter is a Barcelona-based freelance writer for ESPN.com who specializes in La Liga and the Spanish national team. During UEFA's 70 years of European Cup, Champions League , UEFA Cup, Europa League , Cup Winners Cup and Conference League , those competitions past and present have produced in the region of 350 semifinals. From mighty aristocrats like Real Madrid , AC Milan , Liverpool , Barcelona and Bayern Munich , to surprise packages like Aberdeen , Malmö , Reims , Saint-Étienne , Club Brugge , Standard Liege and Dukla Prague. But not once, not by a very long shot, has European knockout soccer seen anything vaguely resembling this Thursday's semifinalists, Rayo Vallecano . The Madrid-based rebel club from a working-class and hard-nosed -- but monstrously big-hearted -- neighborhood of Vallecas.…