Real Sociedad advanced in the Copa del Rey after a 1-0 victory over Athletic Club on March 5, 2026. The match at the Reale Arena was another fiercely contested Basque derby, with a single goal deciding the outcome. Sociedad scored the decisive goal midway through the first half, capitalizing on a well-worked set-piece opportunity. Athletic Club responded with characteristic passion, creating several chances to equalize, but found the Sociedad defense and goalkeeper in inspired form. The home side managed the game intelligently in the closing stages, holding on to secure a narrow but vital win that sent them through to the next round of Spain's premier cup competition.