|18,963 and 26 guns 5,000 – 18 guns||Date 11 December 1868|
|297 dead, 1,366 wounded 3,000 dead, 600 wounded|
Result Decisive Brazilian victory
Similar Paraguayan War, Battle of Ytororó, Battle of Lomas Valentinas, Battle of Tuyutí, Battle of Acosta Ñu
The Battle of Avaí was fought by the stream of the same name in Paraguayan territory in December 1868 during the Paraguayan War, between the forces the Triple Alliance and the Paraguay. Advancing after the Battle of Ytororó, the Allied force made for Villeta.
The Allied advance stopped where the road crossed the stream Avay. For the Allied army, the vanguard consisted of the 3rd Corps, commanded by Gen. Osorio, the 2nd Corps under Gen. Jose Luis Mena Barreto formed the center, and the 1st Corps under Gen. Jacinto Machado Bittencourt formed the rearguard. Caxias also had available the Cavalry Divisions, including the 1st under Gen. Joao Manuel Mena Barreto, the 5th under Col. Jose Antonio Correa da Camara, and the 2nd and 3rd under Gen. Andrade Neves. The battle began at noon and lasted for five hours. The flanking attacks by the 1st, 2nd, and 3rd Cavalry Divisions into the Paraguayan rear made escape impossible. With the total defeat of Gen. Caballero's force, Marshal Caxias reached Villeta. The Paraguayan survivors, less than 50, retreated for Lomas Valentinas. There President Lopez has assembled 3,000 troops, plus another 2,000 at Pikysyry and 700 at Angostura.
President Lopez ordered the evacuation of Asuncion to the provisional capital of Piribebuy.