At the start of the battle she joined Aigle, Neptune and Fougueux, in engaging the second ship in the British lee column, HMS Belleisle.

As San Ildefonso surrendered to HMS Defence, Deniéport took advantage of a light wind to attempt to fill the gap in the line.

This proved hazardous as Achille's abandoned but loaded guns were set off by the intense heat now raging below decks.

The fires eventually reached her magazine and she blew up spectacularly at 5:45 p.m., taking 480 with her, and foundered quickly, her colours high, marking the end of the battle.

The rescue of a female member of her crew named Jeannette after the explosion was the inspiration for the coloured engraving Anecdote At the Battle of Trafalgar.