Hearing of her deeds, the commander-in-chief of Chile's military, General Manuel Baquedano, summoned Morales to meet him and officially authorised her to wear the uniform of a cantinière (as she had done so without authorisation before) and gave her the rank and pay of a sergeant ("sargento segundo", lit. "second sergeant"). She later moved to the 4th Division, in which she served during the Tacna and Arica Campaign. At the Battle of Tacna on 26 May 1880, she continued to provide water to the exhausted men at the front lines after she received a slight wound herself. She was one of the first soldiers to enter the city of Tacna that evening, and soldiers of the Carabineros de Yungay cavalry regiment recalled her riding into the town on a horse, raising her rifle as they passed by and crying "Viva Chile!". After the battle, she was stricken for some time with an illness she picked up from prisoners of war she had cared for, and she wrote a letter to a friend of hers in Antofagasta, assuming she was on her deathbed. Nonetheless, later writers said she was present at the Battle of Arica two weeks later and ordered the mass killing of captured Peruvians, an account also inscribed on a Peruvian memorial to the dead. During January 1881, she fought at the Battle of Chorillos and Battle of Miraflores and was among the Chileans who entered Lima after the city was captured.