The squadron of four galeras, or galleys, was in charge of Captain Diego de Medrado.
Next in command to Medina Sidonia was Don Alonzo de Leyva, captain-general of the light horse of Milan.

Don Francisco de Bobadilla was marshal-general of the camp.

Don Diego de Pimentel was marshal of the camp to the famous Terzio or legion of Sicily.
The total tonnage of the fleet was 59,120: the number of guns was 3165.
Of Spanish troops there were 19,295 on board: there were 8252 sailors and 2088 galley-slaves.

Besides these, there was a force of noble volunteers, belonging to the most illustrious houses of Spain, with their attendants amounting to nearly 2000 in all.

There was also Don Martin Alaccon, administrator and vicar-general of the Holy Inquisition, at the head of some 290 monks of the mendicant orders, priests and familiars.