The so-called "mixed formations" were devised by Wellesley as a strategy to fully utilize the Portuguese Army.
From then on, each unit under his command consisted of thirty percent British soldiers and seventy percent Portuguese soldiers.
In combat, the elite British soldiers stood on the sides and the last row, "encircling" the Portuguese soldiers, constantly reminding them of what they should do.
This way, the originally worthless Portuguese Army could exhibit considerable combat effectiveness.
From the first day Wellesley arrived in Porto, he ordered Beresford to train the Portuguese in batches.
Two months later, he would have over seventeen thousand available soldiers. Together with ten thousand British troops, his total forces would reach nearly thirty thousand.
Chasing the twenty thousand disarrayed Spanish troops would undoubtedly be without the possibility of failure.
