Amfitrite was sailing off the Spanish Atlantic coast in November 1804, when the 74-gun third rate HMS Donegal, then watching the port of Cadiz under the command of Captain Richard Strachan, spotted her.

The engagement lasted only eight minutes, and resulted in a number of deaths, including that of the Spanish captain, who fell to a musket ball.

The Amfitrite surrendered and after being searched, was found to be laden with stores and carrying dispatches from Cadiz to Tenerife and Havana.

On 28 March 1806, a French squadron consisting of the French frigates Guerrière, Revanche and Sirène, and the brig-corvette Néarque, all under the command of Amand Leduc, were dispatched from Lorient, with orders to attack and destroy British and Russian whalers in the Arctic, off Greenland.

Blanche quickly closed the distance, but Guerrière, perhaps mistaking the British frigate for one of her squadron, did not initially take action.

A fierce fight followed, with Guerrière eventually surrendering at half past one that morning, having lost her mizzenmast.

Blanche escorted Guerrière back to Britain, arriving with her prize on 26 July in Yarmouth Roads.

Guerrière was commissioned into the Navy as HMS Guerriere, after a repair and refit that brought her to 48 guns.

In 1847 the Admiralty issued the Naval General Service Medal with clasp "Blanche 19 July 1806" to all surviving members of the crew that claimed it.