Winning the domestic league also granted Athletic entry to the European Cup, the first edition of which had been won by Spanish rivals Real Madrid. During the 1956–57 campaign, They defeated FC Porto in the opening round and were then drawn against Budapest Honvéd of Hungary at a significant point in that nation's history. Before the first leg of their tie – originally scheduled for Budapest – had been played, the Hungarian Revolution of 1956 began. The Honvéd players, who formed the backbone of the 'Mighty Magyars' international side, were already out of the country, but their families remained at home amidst the chaos of the uprising. The legs were switched, with Athletic winning narrowly 3–2 in Bilbao.