[3] A small French frigate squadron, supported by smaller warships and privateers operated from the islands posing a considerable threat to British maritime trade in the Indian Ocean.

[5] Together the ships sailed from Madras on 30 August 1794, stopping at the allied port of Trincomalee in Dutch Ceylon and the undefended French-controlled island of Rodrigues before arriving off Île de France in October.

In 1794 suspected royalists were arrested, including the naval commander Saint-Félix, their executions forestalled by the arrival of news that the French Convention had abolished slavery.

The preoccupation of the naval authorities had prevented any offensive operations and the reduced squadron, now commanded by Captain Jean-Marie Renaud, remained in Port Louis.

[8] The French squadron comprised the 40-gun frigate Cybèle under Captain Pierre Tréhouart, the 36-gun Prudente under Renaud, and the 14-gun brig Coureur under lieutenant de vaisseau Garaud.

[5] Return fire from Centurion managed however so to damage Cybèle that she was unable to retreat in the light winds; the two largely immobilised ships then began a close range duel.

For more than an hour the exchange continued, Renaud unable to intervene from leeward and Smith repeatedly refusing Osborne's orders to support his ship, Diomede remaining at long range and contributing an intermittent and inaccurate fire on the distant Cybèle.

At 17:45, with Prudente close by, the main topmast fell on Cybèle, which had 3 feet (0.91 m) of water in the hold, but Osborne, outnumbered and with his ship damaged, reluctantly withdrew.

With the threat lifted, Renaud was able to take Cybèle under tow and retire in the direction of Île de France,[16] followed distantly and ineffectually by Diomede until night fell.

This panel decided that Smith's behaviour was unacceptable and he was dismissed from the Navy,[24] by which time he had lost Diomede, wrecked on a rock in Trincomalee Bay on 2 August 1795 during the invasion of Ceylon.

[26] On Île de France the relief of the blockade meant that shipping, particularly American vessels laden with food supplies from Tamatave on Madagascar, could reach the island and the threatened famine was averted.