De Montfort, with the idea of charging in on Pedro’s left, worked rapidly north and east around the marsh until he found himself blocked by Pesquies ravine, which the chroniclers describe as a “fossatum” (i.e., a ditch or trench). Cut in the steep banks of this obstacle was a narrow path, blocked at the farther end by a strong Aragonese combat patrol or covering detachment. Such covering detachments were familiar enough, as we learn from the “Siete Partidas” of Alfonzo the Wise of Castile, written about 1260, in which they are called alas or citaras. If it be objected that Pedro was in no mood to think of such details as posting this detachment, we may fairly imagine some grizzled knight of Aragon who knew enough to take on the job by himself with his own immediate followers. To go from line to column and try to force the narrow path in the face of opposition was a bad business, but de Montfort had no choice. Time was passing, he had the marsh on his left and the ravine stretching away on his right. At the head of his men he crossed the ravine and set his horse to scramble up the farther bank. In this unfavourable position, as he struggled to protect himself from the blows he could not yet hope to return, he broke his left stirrup leather—the third time one part or another of his equipment had played him false that day. With great dexterity he kept his seat and, reaching the summit of the bank, unhorsed the nearest enemy with a blow of the fist to the jaw—the Spaniard must have been wearing not a closed pot-helm but an open-faced steel cap. This man seems to have been the detachment commander, for when his followers saw him fall they broke up and fled on the instant. Their flight exposed to Count Simon the left flank of the Aragonese main body. He got his three hundred across, deployed them, and charged. All this time the first two crusading squadrons had been fighting hard. Although their close formation and the fury of their charge had carried them deep into the ranks of their enemies, still these last had not broken, but closed in around them. Strict order and alignment had gone and the fighting was man to man. The knight who had taken the part of Pedro could not equal his master’s prowess, and Pedro himself forgot caution, and cried out: “I am the King.” Whereupon those who had sworn to have his life closed around him and killed him, despite his valor and his skill in arms.