The Civil War broke out on 18 July 1936 and left the Viejo Chamartín in a terrible state. A large sum of money had to be invested to repair the extensive damage. In October 1939, it was reopened for the first post-war derby, in which Los Blancos beat Atlético de Madrid 2-1. The fan base didn't decline during the war, and the stadium was packed to capacity. After successive renovations, the stadium was enlarged to a total of 25,000 seats, but this was not enough to meet the huge demand of fans. 

Santiago Bernabéu had been dreaming of building a new stadium for many years and when he became president in 1943, he made it a reality. He set in motion a great pharaonic project, with a capacity for 100,000 spectators. An impressive stadium in which the most brilliant pages of Real Madrid's history would be written. The Nuevo Chamartín became the best stadium in Europe and one of the most modern in the world. At its inauguration in December 1947, the Madrid side beat Portuguese champions Os Belenenses (3-1). Barinaga was the scorer of the first goal scored at the stadium. 

This was a period of continuous improvements to the stadium, which was to become the Santiago Bernabéu.