Sir Maurice Fitzgerald—a Desmond dependent resident in the borderland between the territories—had during the ebb and flow of the dispute between the Butlers and the Fitzgeralds declared his intention to accept the protection of his first cousin, Thomas Butler, Earl of Ormonde, 

Gerald Fitzgerald, Earl of Desmond, musters the Geraldine forces in January 1565 in order to coerce him back into dependency, and marches east across Munster and into the territory of the Decies in Waterford.

Ormonde mobilizes his men to intercept the Geraldines at Affane, a ford over the Finisk tributary of the Blackwater River, in the foothills of the Knockmealdown Mountains near Lismore.

Here, the rival forces fight a pitched battle against each other in a blatant defiance of the Elizabethan state's law.

After Desmond is wounded and thrown from his horse, the Geraldine troops are routed and pursued by the Butlers to the riverbank.

About three hundred Geraldines are killed, with many drowning as they are intercepted by armed boats in crossing the river.

Desmond is taken in captivity to Clonmel and then to Waterford city, where Lord Justice Arnold takes custody of him after a legal wrangle with Ormonde.