Elliot went out with Admiral Sir George Rodney's fleet to relieve Gibraltar in 1780 and took part in the defeat of the Spanish fleet under Juan de Lángara at the Battle of Cape St Vincent on 16 January 1780. "Edgar" played a large part in the fighting, suffering casualties of six killed and 20 wounded, the third highest casualty figures of the British ships. Having temporarily relieved Gibraltar, Rodney took his fleet to the West Indies, but left Elliot and "Edgar" at Gibraltar to support the garrison there. Captain Erasmus Gower was appointed as his flag captain. Elliot soon found that there was little assistance that he could render, and having a ship as large as "Edgar" on station there made her a target for Spanish gunboats. Rodney was rebuked for leaving him there, as it was against his orders, and necessitated sending a frigate to order his return. Elliot consequently returned to England.