Both armies have orders to advance to engage the enemy.
The result is an encounter battle between 1st British and 6th French corps at Chaves.
The French outnumbered the British in infantry, and due to the terrain the battle would be decided by town fighting. The leading brigades entered the town and commenced to skirmish. The French quickly won the fire-fight, and the British brigade routed with 800 casualties.
The reserve British brigade were poor quality conscripts, and they did not have any supports. Seeing the leading brigade break and run they quickly took fright and joined the rout.
A bad start to the campaign for Wellington.