Now, after Cristofano had spent some time drawing under the discipline of Raffaello, there arrived in the Borgo the painter Rosso, with whom he contracted a friendship, and received some of his drawings; and these Doceno studied with great diligence, considering, as one who had seen no others but those by the hand of Raffaello, that they were very beautiful, as indeed they were. But these studies were broken off by him, for, when Giovanni de' Turrini of the Borgo, at that time Captain of the Florentines, went with a band of soldiers from the Borgo and from Città di Castello to the defence of Florence, which was besieged by the armies of the Emperor and of Pope Clement, Cristofano went thither among the other soldiers, having been led away by his many friends. It is true that he did this no less in the hope of having some occasion to study the works in Florence than with the intention of fighting; but in this he failed, for his captain, Giovanni, had to guard not a place within the city, but the bastions on the hill without. That war finished, and the guard of Florence being commanded not long afterwards by Signor Alessandro Vitelli of Città di Castello, Cristofano, drawn by his friends and by his desire to see the pictures and sculptures of the city, enlisted as a soldier in that guard. And while he was in that service, Signor Alessandro, having heard from Battista della Bilia, a painter and soldier from Città di Castello, that Cristofano gave his attention to painting, and having obtained a beautiful picture by his hand, determined to send him with that same Battista della Bilia and with another Battista, likewise of Città di Castello, to decorate with sgraffiti and paintings a garden and loggia that he had begun at Città di Castello. But the one Battista having died while that garden was being built up, and the other Battista having taken his place, for the time being, whatever may have been the reason, nothing more was done.
Meanwhile Giorgio Vasari had returned from Rome, and was passing his time with Duke Alessandro in Florence, until his patron Cardinal Ippolito should return from Hungary; and he had received rooms in the Convent of the Servites, that he might make a beginning with the execution of certain scenes in fresco from the life of Cæsar in the chamber at the corner of the Medici Palace, where Giovanni da Udine had decorated the ceiling with stucco-work and pictures. Now Cristofano, having made Giorgio's acquaintance at the Borgo in the year 1528, when he went to see Rosso in that place, where he had shown him much kindness, resolved that he would attach himself to Vasari and thus find much more opportunity for giving attention to art than he had done in the past. Giorgio, then, after a year's intercourse with him as his companion, finding that he was likely to make an able master, and that he was pleasant and gentle in manners and a man after his own heart, conceived an extraordinary affection for him. Wherefore, having to go not long afterwards, at the commission of Duke Alessandro, to Città di Castello, in company with Antonio da San Gallo and Pier Francesco da Viterbo (who had been in Florence to build the castle, or rather, citadel, and on their return were taking the road by Città di Castello), in order to repair the walls of the above-mentioned garden of Vitelli, which were threatening to fall, he took Cristofano with him, to the end that after Vasari himself had designed and distributed in their due order the friezes that were to be executed in certain apartments, and likewise the scenes and compartments of a bath-room, and other sketches for the walls of the loggia, Gherardi and the above-named Battista might carry the whole to completion. All this they did so well and with such grace, and particularly Cristofano, that a past master in art, well practised in his work, could not have done so much; and, what is more, experimenting in that work, he became facile and able to a marvel in drawing and colouring.