On May 10, Bartolommeo Colleone crossed the Po. The lords of Mirandola and Carpi, Ercole of Este, and the Count Deifebo of Anguillara, who had been banished by the Pope, and was son of the old disturber of the environs of Rome, had joined him immediately. On his further march, the Ordelaffi of Forli and Alessandro Sforza of Pesaro came to him, the latter of whom, won over by Venice, opposed his own nephew; while Astorre Manfredi faithlessly turned his back upon Florence. Colleone’s army soon numbered 8,000 horse and 6,000 foot. Galeazzo Maria Visconti, persuaded by the representations of the Count of Urbino, now first set out with his troops and marched against the Count by way of Bologna, from whence men were sent to reinforce the allies. The general of the latter, now of equal strength with Colleone, would willingly have given battle; but he, on the one side, true to the old system of marches and counter-marches, avoided a decision, and on the other the presence of the Duke of Milan, whose experience did not equal his rank and claims, hindered the allied commander in his movements. At last Sforza was persuaded to visit Florence, and yield the command to Roberto da Sanseverino. Meanwhile the Count of Urbino attacked the enemy on July 25 at Molinella, in the territory of Imola. From a skirmish of the outposts of both armies a general battle arose, which was all the more bloody because light field-pieces were employed, and a Milanese troop of horse was enticed into an ambuscade; whereon, the Count, whose horse had been killed under him, commanded that no quarter should be given. The fight lasted for seven hours, in which, according to one of the lowest estimates, 300 men and 400 horses were killed—a great number for Italian warfare at that time. At nightfall they ceased to fight on Colleone’s proposal, and then the Count of Urbino and Alessandro Sforza, whose son Constanzo was amongst the prisoners, rode up to one another and shook hands.