In 1710, at the age of seventeen, he joined the Spanish Army as a cadet, and in 1717 he transferred to the naval infantry, as a member of which he participated in the capture of Sicily in July 1718, during the War of the Quadruple Alliance.

He was promoted to Captain in 1733 and took command of the frigate Galga,[2] which as part of the fleet of the Marquis of Clavijo captured Naples during the War of the Polish Succession.

In that opportunity, he personally landed and led a force composed of 200 men from his ship and 100 naval infantry to capture the fortress.

After the battle he sailed back to Naples, where he was personally congratulated by the Infante Don Carlos for his outstanding valor and performance in battle, and was rewarded with the title of Marquis of Brindisi[2] (in most literature he appears credited as Marquis of Ovando, which is simply a corruption of his title and his last name), was promoted to Lieutenant Colonel and was given the command of the Man-of-war El León, of seventy cannons.

[1] He immediately returned to his fleet command on board of the ship San Fermín and departed to chart the Juan Fernández Islands.