Learning of the Angevin maneuver, Roger of Lauria set out to look for Admiral Reynald Quarrel. He arrived off Naples on June 16th with only 44 galleys. Despite the numerical inferiority of the Catalan-Aragonese fleet, the Angevins were reluctant to come out and fight. It appears that Roger had to prod the Angevin commanders into action by parading the fleet past the beached Angevin galleys while hurling arrows and insults at them. The taunting appears to have been too much for the Angevins and their commander Count Robert of Artois, for with a large number of the counts and knights of the realm on board, the Angevin fleet put out to meet the Roger on June 23, 1287. As at Las Formigueras, at first contact the Genoese admiral Henry of Mari fled the battle with his squadron (For more on Genoese behavior in the war see: Trade as a Weapon article). In the ensuing confusion the Angevin fleet disintegrated and lost 44 galleys and over 5,000 prisoners. More importantly, a large portion of the nobility was captured, which led to the conflict being called the Battle of the Counts. Among the captured were Admiral Reynald III Quarrel of Avella, Hugh of Brienne, the Count of Aquila, Guy de Montfort (Count of Nola) and Count Jean de Joinville (author of Histoire de Saint Louis). With the defeat of the Angevin fleet, the forces in Castello Svevo at Augusta were cut off and forced to surrender. This battle proved to be the final blow to the Angevin cause and for the rest of the war the ships of the Regno played only a minor role in the conflict.
With his stunning victory, Roger was in a position to control the whole area. The Sicilians urged Roger to take and sack Naples and the surrounding areas, but instead Roger ransomed off the captives and concluded a truce with Robert of Artois. The Sicilians were highly critical of this, with Speciale stating accusingly that Roger "not considering this (the sacking of Naples), but contemptuous of nearly everything, having accepted large amounts of money, signed useless treaties with the enemy without having consulted the king." In fact, existing fleet accounts show that Roger acted with the approval of Alfonso III and with good reason. As always it came down to money. The crews had not been paid for several months and Roger knew that keeping the mercenary contingent of the fleet under control would become increasingly difficult. The other factor was that the fleet was not organized for an amphibious operation against a large city. Roger had retaken possession of the islands of Ischia and Capri off Naples and was in a good position to set up an effective blockade of the city. Moreover, the truce fit the needs of Alfonso who was looking for a way in which to disengage himself from the conflict.
