While Nuno Álvares was pondering these matters in Évora, a message arrived from his liege lord the Master in which he was informed that 600 lances had left the King of Castile's encampment to join up in Crato with the other troops who were already there, to go and do battle with him, and that he commended him to God. The Master also sent money for a month's wages, which were very much needed at that time. Immediately after this message, another arrived for Nuno Álvares to the effect that his brother the prior, along with Pedro Sarmiento, Juan Rodríguez de Castañeda and the Count of Niebla, plus the Master of Alcántara, who had become master after the death of his predecessor who died in the battle of Fronteira, and Martim Eanes de Barbuda, who styled himself Master of Avis, as well as other noblemen and squires, in all 2,500 lances, 600 light horsemen and many foot soldiers and crossbowmen, had all gathered in Crato. There they were, taking care of all arrangements needed to enter the Alentejo, to come and seek him out, and to challenge him to battle. Hence, they planned to rob and raid the entire Alentejo region, in the worst manner that they could.

Nuno Álvares immediately sent word throughout the district to gather more troops. In all, there were 530 lances, and 5,000 between foot soldiers and crossbowmen. In the meantime, the said Castilian lords departed with all their forces from Crato, ravaging the land, until they arrived at Arraiolos which, according to some, was attacked and taken by force. But those who speak with greater accuracy about this say that it was delivered to them by some unworthy Portuguese, among whom the principal figure was Gonçalo Mendes de Oliveira, a kinsman of the queen [Leonor Teles].

From there, Pedro Sarmiento sent a knight of his company, one García González de Herrera, bearing a most intemperate letter to Nuno Álvares, of which the latter took no notice and to which he refused to reply. He also brought him a two-handed sword and said that he was to give it to Nuno Álvares as a gage, and to challenge him on his behalf to come to battle because he intended to give his arse a good whipping as one does to a boy.