The men and guns of the Brazilian vessels had been landed to reinforce the fort, and the resulting confrontation was an inconclusive cannon duel, as a ground attack by troops from the Banda Oriental failed to materialize.

The night assault, supported by gunboats, was repelled after a bloody combat in which the Argentine troops suffered heavy losses but succeeded in destroying one Brazilian ship.

During this last battle, the concentrated fire of a number of Brazilian vessels succeeded in knocking the major Argentine frigate 25 de Mayo out of action.

On 12 May in Montevideo, admiral Rodrigo Pinto Guedes replaced Ferreira Lobo in command of the Brazilian naval forces operating in the Río de la Plata sector, often called the Equadra do Sul (Southern Squadron).

He put captain James Norton in command of a squadron (the Divisão Bloqueio) whose mission was to definitively blockade the strategic port of Buenos Aires.

Another squadron (the Third Division), led by Jacinto Sena Pereira, was ordered to control the Uruguay river and thereby cut supply and communication lines between the Argentines and their army in the Banda Oriental.

On 15 November, in command of a fleet of some 13 vessels carrying 33 guns and approximately 1,000 men, Mariath defeated the republican forces under Giuseppe Garibaldi at Laguna.