Promoted to lieutenant colonel he led the Republican Army at Boadilla, Corunna Road, Guadalajara and Segovia. By 1938 he was commander of the First Corps of the Army of the Centre.
In February, 1939, Juan Negrin promoted communist leaders such as Antonio Cordon, Juan Modesto and Enrique Lister to senior posts in the army. Segismundo Casado, commander of the Republican Army of the Centre, now became convinced that Negrin was planning a communist coup. On 4th March, Casedo, with the support of the socialist leader, Julián Besteiro and disillusioned anarchist leaders, established an anti-Negrin National Defence Junta.
On 6th March José Miaja in Madrid joined the rebellion by ordering the arrests of Communists in the city. Juan Negrin , about to leave for France, ordered Barceló to try and regain control of the capital. His troops entered Madrid and there was fierce fighting for several days in the city. Anarchists troops led by Cipriano Mera, managed to defeat the First Corps and Barceló was captured and executed.