Theodore Laskaris, who had been troubled by his defeat at Battle of Poemanenum, collected as many people as he could from around Nicaea and assembled a large army.
The two sides engaged in close hand-to-hand combat, with victory falling to the Franks, who killed or captured much of the Byzantine army.
According to Niketas Choniates, the commander of the Byzantine forces was not Constantine Laskaris, but Theodore Mangaphas, a usurper who held the city of Philadelphia.
Henry, convinced that he had to make a desperate attempt, drew up his cavalry in battle array, and raising their lances, they awaited the Byzantine attack.
At a given signal, Henry leaped ahead of the others and rode his horse through the centre of their ranks, while his cavalry, couching their lances and raising the war cry, scattered the Byzantines and pressed upon them as they retreated.