(March 27, 1351), episode in the struggle for the succession to the duchy of Brittany between Charles of Blois, supported by the King of France, and John of Montfort, supported by the King of England. The combat at arms was celebrated by an unknown trouvère and retold with variations by Jean Froissart.

When, in spite of a truce, John Bramborough, the English captain of Ploërmel, continued his ravages in the district of Josselin, Jean de Beaumanoir, captain of Josselin and marshal of Brittany, sent Bramborough a challenge. Thus on March 27, 1351, a fight took place near Ploërmel, with 30 picked champions, knights and squires, on either side. Beaumanoir's side comprised 30 Bretons, Bramborough's 20 Englishmen, 6 German mercenaries, and 4 Brabançons. The battle, fought with lances, swords, daggers, and maces, is reminiscent of the last fight of the Burgundians in the Nibelungenlied, especially in the advice of Geoffroy du Bois to his wounded leader, who was asking for water: “Drink your blood, Beaumanoir; that will quench your thirst!” The victory was decided by Guillaume de Montauban, who mounted his horse and overthrew seven of the English champions, the rest being forced to surrender. All the combatants were either dead or seriously wounded, Bramborough being among the slain. The prisoners were well treated and released for a small ransom.