In July 1570, the Oda-Tokugawa allies marched on Yokoyama and Odani Castles, and the combined Azai-Asakura force marched out to confront Nobunaga. Tokugawa Ieyasu joined his forces with Nobunaga, with the Oda and Azai clashing on the right while Tokugawa and Asakura grappled on the left. The battle turned into a melee fought in the middle of the shallow Ane River. For a time, Nobunaga's forces fought the Azai upstream, while the Tokugawa warriors fought the Asakura downstream. After the Tokugawa forces finished off the Asakura, they turned and hit the Azai right flank. The troops of the Mino Triumvirate, who had been held in reserve, then came forward and hit the Azai left flank. Soon both the Oda and Tokugawa forces defeated the combined forces of the Asakura and Azai clans.