Excavations inside the church clarified, as far as was possible, the aspects of the complex’s evolution that had remained problematic.

The identification of the church’s first layout (phase 1) was fundamental. Its east-facing semicircular apse and two stretches of the long sides of the single nave, dating at least from the 13th century, were preserved. Due to the lack of traces of the façade the length of this early church could not be calculated.

From other historical data it can be deduced that this church remained in use for several centuries, from the end of the 13th century until just before the period from which the frescoes on the back wall of the apse date, which obliterated the first church (1513).

Between the end of the 15th century and within the first quarter of the 16th century the church was certainly restructured according to a plan that was only partly completed, in two different but close periods of time. The original plan foresaw the complete demolition of the presbytery to make room for a much more imposing square apsidal structure, including a semi-interred level. However, during the course of the work this plan was abandoned and the semi-interred space was not constructed. The northern perimeter wall of the original church was kept whilst the southern wall was partially demolished and partially reused in a new, wider foundation. The nave was built to its present length (10.30 m).

In this phase the church was already used for funerary purposes, as attested by the presence of 13 tombs with stone coffins. Within a short time the church was again modified reaching its definitive width (8.80 m). This led to the demolition of the earlier north and south perimeter walls and the partial insertion of a bell-tower in the nave. The two-storeyed sacristy was not built until 1732.