A 1980-1981 restoration of the wall of the Palazzo Pubblico (Siena) which bears the fresco of <i>Guido Riccio de Fogliano at the Siege of Montemassi</i> uncovered a 14th century fresco, but involved the removal of a part of <i>Guido Riccio</i>'s border. The border had uncovered a portion of the newly discovered fresco which sustained damage during the late 14th or early 15th century. A reevaluation of the dating of <i>Guido Riccio</i> was necessitated by these discoveries -- AATA