The action of 18 March 1748 was a naval engagement during the War of Jenkins' Ear in which a fleet of six Royal Naval vessels captured a number of merchantman in a successful engagement against a Spanish convoy escorted by nine ships of the line and frigates.

[2] Six British warships were patrolling off Cape St. Vincent under the command of Captain Thomas Cotes.

They ranged in size from the 70-gun HMS Edinburgh, under Cotes's command, through the 60-gun Eagle, Windsor, and Princess Louisa, to the 24-gun Inverness and the frigate Gax.

[1] The escorting Spanish ships of the line were Soberbio (74), Leon (74), Oriente (70), Colorado (70), Brillante (64), Pastora (64), Rosario (60), Xavier (54) and Galga (54).

[2] The rest of the convoy managed to escape under cover of darkness with their escorting ships.