The Channel Fleet accompanied the convoy for several hours, to a point 112 leagues off the Isles of Scilly, where the two groups of ships parted company.

This information had been collected by the network of secret agents created by Juan de Miralles and based in Philadelphia, Following the instructions given to Luis de Córdova by Don Jose Moñino, count of Floridablanca, the Spanish fleet set sail from Cádiz and sailed as far as Madeira and the Canary Islands, where Don Luís deployed several frigates to spot the convoy.

When strange sails (those of the Spanish fleet) were spotted, Captain Moutray signalled his ships to alter course and follow him close to the wind.

[19] The 120-gun ship of the line Santísima Trinidad, the flagship of Admiral de Córdova, fired on Mountstuart and Godfrey to induce them to strike.

A frigate flotilla, commanded by Santiago de Liniers, and part of the Concepción squadron, captured the 30-gun East Indiaman Hillsborough.

[20] This was a major intelligence failure, for the British Admiralty did not learn of the presence of an enemy fleet at sea until 4 August, and neither did Geary nor Captain John Moutray.

[24] This Spanish victory, compounded by the serious storm losses in the Caribbean, produced a financial crisis among marine insurance underwriters throughout Europe.

Insurance company Lloyd's, one of the his investments, suffered great losses having to face redemption of policies worth more than half its assets and lost 60 per cent of its market cap.

Public discontent in Great Britain also increased against the British prime minister Frederick North; who was also Chancellor of the Exchequer as well as the Royal Navy leadership.

This successful interception by enemies showed that the English fleet, dispersed in too many theaters of operations,had lost control of the Atlantic routes in 1780.