The 2009-10 campaign delivered heartbreak and turbulence for Real Valladolid as Pucela finished a crushing 18th in La Liga, resulting in relegation after a three-year stay in the top flight. The season was defined by extreme instability, featuring three different head coaches, José Luis Mendilibar, Onésimo Sánchez, and finally Javier Clemente, in a desperate attempt to survive. Leading the line was the emerging, aggressive forward Diego Costa, whose 8 league goals proved vital but ultimately insufficient. Their fate was sealed on the final day with a crushing 0-4 loss to league champions Barcelona at the Camp Nou, marking a defining and painful chapter in the club's modern history.