The King of Castile left Seville once more, at the beginning of 1364 in the fifteenth year of his reign, invading Aragon via the kingdom of Valencia and capturing Alicante and other townships. On arriving at Burriana, he noticed a number of galleys and other ships bringing to [the city of] Valencia provisions which were desperately needed. He therefore deviated from his journey in order to prevent their arrival and pitched his camp at a place known as the Grao, which is next to the sea and half a league from the city. There, every day, he awaited his fleet and the Portuguese galleys which were due to come to his aid. They were all in Cartagena already, but the weather had not yet allowed them to depart.

While King Pedro was without news of the King of Aragon, a squire arrived to inform him that the King of Aragon and Count Enrique, along with all the other great lords and armies, which probably amounted to 3,000 horsemen, as well as many foot soldiers, were approaching in great secrecy and were intent on doing battle with him before he left that place. Moreover, keeping pace with them at sea were a dozen galleys and other ships bringing supplies; to avoid discovery, they had not lit any fires for three nights and on the following day they would confront him.

On hearing this, the king left at once and went to Murviedro, which lay 4 leagues away. On the morning of the following day the King of Aragon arrived with all his men. They set up camp between Murviedro and the sea, at a league away from the town, whilst their galleys and ships lay close at hand [as they travelled down the coast to Valencia]. In that way the city received aid both by land and by sea.

After twelve days the King of Castile's fleet arrived, comprising twenty of his own galleys and forty naos, as well as ten galleys from Portugal, sent by his uncle to help him. The Aragonese fleet, on seeing the Castilian vessels, were stricken with fear and headed up the River Cullera. King Pedro went aboard his fleet at once and stationed them at the mouth of the river, planning to seize the Aragonese galleys.