His presidency was short lived, he had only time to assemble a War Council in which it was decided to assemble a 600 manned army led by Mejía and head south and face the forces of Juan Sámano. Mejía faced Sámano in the Battle of Cuchilla del Tambo which culminated with the defeat of the patriots on June 29. Mejía escaped to La Plata where he ceded his presidential powers to Custodio García Rovira, thus assuming the vice presidency as first intended.