Imperial engineers open breaches in the walls of Mirabello in the early morning of February 24, 1525, allowing Lannoy's forces to enter the park.
At the same time, Leyva sorties from Pavia with what remains of the garrison.
In the ensuing four-hour battle, the French heavy cavalry, which had proven so effective against the Swiss at Marignano ten years prior, masks its own artillery by a rapid advance and is surrounded and cut apart by landsknechts and d'Avalos's massed Spanish arquebusiers.
Meanwhile, a series of protracted infantry engagements results in the rout of the Swiss and French infantry.
The French suffer massive casualties, losing the majority of their army.
Among those killed are Bonnivet, Jacques de la Palice, La Trémoille, and Richard de la Pole, the last member of the House of York to actively and openly seek the crown of England, while Anne de Montmorency, Robert de la Marck, and Francis himself are taken prisoner along with a host of lesser nobles.
