His Spanish brigade included one battalion each of the Irlanda and Cantabria Infantry Regiments, one company of Cazadores (sharpshooters), 120 gunners, and 25 cavalrymen.

Overlooked at short range by higher ground, with walls unprotected against artillery fire, it would easily fall to a serious attack.

Captain C. F. Smith of the Corps of Royal Engineers strongly opposed the idea; he had noted that inside the walls, the ground level was much lower which combined with a deep narrow river that flowed through the town would make that assault quite hazardous.

The night of 29/30 December had very heavy rain, with the portcullis defending the river entrance bent inwards by the flood of water and the defences requiring quick repairs before the French attacked at dawn.

French Grenadiers advanced along the now dry river bed trying to enter through the portcullis, however it held and the 87th Regiment blunted their attack with withering fire.

[5] This was the only attack that was made, the weather became extremely inclement for several days, the torrential rain damaging the French batteries and trenches so that on the night of 4 January 1812, they were heard pulling back.

General Copons went on to fight many more battles alongside the British, his shining star failing on the return to Spain of King Fernando VII.