1200 23rd August 1813
General Packenham had orders to attack Castrillo with his 2nd British division. But as he prepared to advance at first light he could see the Westphalian division moving to attack him. He ordered his division to take up defensive positions until the Espana arrived with his 1st Spanish division to support him. In the meantime he unlimbered his artillery to fire on the French troops holding Castrillo
It was midday before 1st Spanish division was in position and ready to advance on Castrillo. Graham was disappointed that the British gunners had failed to cause any casualties amongst the French defenders, and he was unwilling to order the Spanish to advance against steady French infantry.
The Spanish gunners opened fire at long range and caused 10% casualties to the French chasseurs on the extreme right. They failed their morale and were shaken. The Spanish irregular lancers immediately charged the chasseurs, who broke and ran. The nearby French square fired on the lancers, who also withdrew shaken. This was sufficient for Graham who ordered Espana to advance and attack the town.
On the opposite flank the British line came under fire from the Westphalian gunners. One brigade was in square because of the Westphalian lancers, a second was in line to bring maximum firepower to bear on the approaching infantry. The line suffered 20% casualties, but held their morale. A third brigade was sent to reinforce the line against the Westphalian attack.
By noon all four divisions were in contact and the crisis of the battle was approaching.