 On 18 August , Porto Alegre received instructions from Mitre to attack the Paraguayan fort at Curuzú . The operation would be carried out under the command of Tamandaré . Porto Alegre not only refused to defer to his cousin , arguing that both held the same rank , but also warned that he would operate by himself at Curuzú . Porto Alegre was incapable of submitting his forces to foreign direction and was unwilling to comply with orders issued by the allied commander . Nor was the situation among the allied forces improved once Porto Alegre and Tamandaré found common ground in their distaste for the Brazilian commander of the 1st Corps , Field Marshal Polidoro Quintanilha Jordão ( later the Viscount of Santa Teresa ) . Jordão was ostracized for supporting Mitre and for being a member of the Conservative Party , while Porto Alegre and Tamandaré were Progressives . 
