It could still have been defended with every prospect of success by a determined general, but the two best Imperialist commanders were hors de combat, and Maximilian of Bavaria, the nominal generalissimo, had no military experience.

The army, too, was disheartened by the first success of the Swedes and by the loss of the general whom they regarded as well nigh invincible.
Tilly had now recovered his senses, but was suffering intense agony from his wound, and on being consulted by Maximilian he advised him to fall back, as the destruction of his army would leave the whole country open to the Swedes.
The Imperialists accordingly evacuated their position and fell back in good order during the night on Neuberg, and then to Ingolstadt.

Rain and Neuberg were occupied the next day by the Swedes.

Gustavus despatched Marshal Horn to follow the retreating enemy to Ingolstadt, and he himself with the rest of his army marched up the Lech to Augsburg, which was held by Colonel Breda with four thousand five hundred men.
The Imperialists had broken down the bridge, but Gustavus immediately built two others, one above and the other below the city, and summoned it to surrender.

Breda, hearing that Tilly was dying, Altringer severely wounded, and that no help was to be expected from Maximilian, considered it hopeless to resist, and surrendered the town, which Gustavus, attended by the titular King of Bohemia and many other princes, entered in triumph on the following day, April 14th.