[2] Advancing from Elvas and passing the river Caya (Caia in Portuguese) the Anglo-Portuguese army had in front the Spaniards commanded by the Marquis de Bay.

The Portuguese cavalry was routed with but slight resistance, and it left exposed two battalions of English foot, which were thus cut off and compelled to lay down their arms.

[1] After the defeat at the Battle of Almansa, the British situation was desperate, they were no longer present in the south-eastern territory of Spain and had minimum or no influence in the course of the war.

Knowing that France had withdrawn some troops as a consequence of defeats of Louis XIV in Flanders, his Anglo-Portuguese army crossed the border near the fortress of Campo Mayor, composed of maximum 20,000 Portuguese and 8,000 English, towards Badajoz.

While his enormous supply train crosses the river Caya, the Anglo-Portuguese made contact with the vanguards of the Spanish cavalry in the fields of Gudiña.

The allies, according to the Portuguese account, were 49 regiments of infantry and cavalry, against only 40 on the side of their Spanish opponents; according to the London Gazette, No 4538, about 17,000 foot and 5,000 horse in very good order, and, by the reports from the deserters, much superior in number to the enemy.

The Portuguese and British were severely defeated, with the loss of about 1,700 men killed or wounded, about 2,300 prisoners, 17 cannon, 15 colours or standards, as well as tents, and baggage.

[3] The Allies were thus disappointed in the preparations they had made, of being able, through their superior numbers, to capture Badajoz, and had the additional mortification to witness above 30 leagues of the Portuguese territory placed under contribution by the Marquis de Bay, who subsisted his army at the expense of his adversaries, by the end of this campaign.

[2] So generally discreditable to the British did their intelligence from Portugal appear, that a contemporary London annalist says: "For my part, I think the stories, and excuses, sent us from thence, are as mean, and poor, as our fighting, and conduct, seem to be."