They had dug the mine that we told you about over the space of many days, until it had reached beyond the wall between the town and the castle. In order to be able to estimate where they were, they brought up two very stout augers suitable for this task and with one of them they made a hole through to the surface, so that they could see for certain where they had got to; with the other one they filled the hole in with mud so it would not be discovered. Thus they broke in with the mine so close to the church that the bell tower was already in sight.

With great pleasure the Master thought that he would seize the town the next day and had those he judged to be suitable for such work made ready, such as João Gomes da Silva and others, telling them they were to emerge in the churchyard and thus make their way into the town where their enemies were. Juan Duque had already been warned where the mine was and where it would come out by the Master's aforementioned disloyal counsellors. Knowing everything about what was being done, very early in the morning the Castilians raised a tent over the spot where the Portuguese planned to gain entry, starting to block it in such a way that the two sides started to come to blows. Each side in order to get its way was put to great toil, so that they grievously wounded one another.

Those above prevented any exit with boards and planks, and those inside set fire to them; in turn water was thrown down to put out the fire. The Master then ordered a cannon to be set up in the mine, but although missiles did hit the wooden boards, splitting them and inflicting damage, it was not enough for the Master's men to achieve the objective with which they had started out. After much labour and injuries on both sides, they stopped fighting.

Seeing that, however much work had been done during all that time, it had all been in vain, the Master was most distressed. He ordered a mine to be dug under the wall of the town.