The next master of whom there is information was Alvar Martínez (in some sources called González), who was quantity surveyor of the Olihuelas limestone quarries at the boundary of Olías del Rey.
Proti koncu 14. stoletja je obstoj mojstra Rodriga Alfonsa očitno dokumentiran; je položil prvi kamen samostana leta 1389, pod pokroviteljstvom nadškofa Pedra Tenoria, ki je umrl deset let pozneje.