 According to Vasari, he was portrayed in the Sassetti and Tornabuoni Chapels painted by Domenico Ghirlandaio, who was his brother-in-law and master.In 1485 he worked in San Marco, Florence, executing much of the painting under the direction by Ghirlandaio.It is believed that Mainardi contributed to the frescoes in the Abbey of Passignano in Val di Pesa, near Florence.