Today there is nothing left of the church of the Counts Guidi: the current building, in fact, from the external lines of neoclassical flavor, is the result of a 19th-century reconstruction. A plaque on the façade commemorates that the economic enterprise of constructing the new church was supported, in 1838, by the parish priest, Lorenzo Picchiotti, and by “members of the community", the souls of the community of San Donato in Greti. The façade, divided into three parts by four pilasters, has a simple entrance portal in wrought pietra serena. The one-room building, with a single nave covered with wooden trusses, culminates, in the apsidal area, with the tribune crowned by a small dome. To complete the neoclassical style of the interior we find the two lateral columns of the Ionic order, based on the steps leading to the presbytery, which support the arch that divides the roof of the building from the dome. The building is surmounted by a small bell gable housing two bronze bells, which, on the basis of the gothic inscriptions appearing on them, must have belonged to the older church, being artifacts datable to the 14th century. Inside there are three altars consisting of just tables, of recent construction. The most valuable work is certainly the 16th-century painting, mentioned by pastoral visits, placed above the main altar, from 1549, the Madonna con il Bambino tra i santi Donato e Antonio Abate. The presence of the titular saint confirms that the work was carried out specifically for the church of San Donato in Greti, and was attributed by Paolo Benassai to a work from the 1420s by Florentine painter Giovanni Antonio Sogliani. On the main altar, today there is a 19th-century wooden crucifix carved in the round, of the Florentine school, while along the side walls we can admire the engravings of Luigi Sabatelli depicting the Stations of the Cross.