After being informed that Lefebvre had left Badajoz with his entire army, Moore began to advance through the difficult terrain on the right bank of the Rio Guardiana intending to bypass the invincible fortress of Badajoz (according to the rules British, Portuguese and Spanish troops are in supply in this area whereas French troops are not). Moore also sent a message to Castanos, the commander of the Spanish Army of Andalusia, to unite both forces at Medellín.

 

But the approach of both armies was too slow to achieve this objective. Before either of their armies reached Medellín, Lefebvre returned with his corps. The Spanish army did not intercept Lefebvre’s IV Corps that marched through Medellín to Badajoz. The Spaniards wanted to cut off his supply afterwards. IV Corps reached Badajoz and crossed the river, forcing the British-Portuguese army, which was operating to surround the city, to deploy for battle. Meanwhile Castanos was about to take control of the road from Badajoz to Medellín, when he realised that another French Corps was approaching from Medellín. 

 

Thus the double battle near Badajoz begins, on the right bank the sub-battle between the British-Portuguese Army and the French IV Corps near Fuerte (Fort) de San Cristobal, on the left bank the sub-battle between the Spanish Army of Andalusia and the French III Corps in the Sierra de San Miguel.