The kaid of Zaragoza had been a participant in the campaign of Galib ibn Abd al-Rahman in the spring, but he appears to have left the expedition before the victory at the Battle of San Esteban de Gormaz in 978.

The forces of the Kingdom of Pamplona, under Sancho II Garcés Abarca, Ramiro's half-brother, were also engaged at Gormaz, where they were defeated alongside the Castilians under García Fernández.

In effect, little time passed before the alarm was given that the enemy had appeared beside the town of Estercuel (a half a day's ride from the city of Tudela, on the royal road that comes up from Zaragoza) and before some Christian cavalry forces had scattered throughout the region, to the right and to the left, in the manner of a raid, and were going about seizing whatever booty they encountered and taking captive five men who were out fishing in those valleys.

[4] From the captive the kaid learned that the Christian army numbered some 500 cavalrymen who had marched from Sos, Ramiro's chief castle, thinking that the governor of Zaragoza was away in Gormaz.

Probably this chase took place over the semiarid Bardenas mountains, terminating in the wooded valley of the river Aragón, in the region of Carcastillo, Murillo el Fruto, and Santacara.