Eventually, there was a firefight, lasting about 90 minutes. Initially the English forces advanced and despite heavy return fire, some of the Irish forces believed they should retreat as they had not expected to engage the English vanguard in open battle. However, MacDermott noticing the heavy casualties the initial fusillades had caused in the English ranks, ordered his pipers to continue sounding battle songs and believed he could destroy Clifford's entire force. At this point, the English forces began to waver and their advance was halted as the Irish muskets and archers continued to pour fire into their ranks. The English musketeers – running low on gunpowder and ammunition – retreated, leaving their infantry under intense Irish fire. At this point Radcliffe had been wounded by a gunshot to the face and another to the leg. He ordered Henry Cosby, the Anglo-Irish son of Francis Cosby, to lead an attack but it soon became clear Cosby had no desire to. While being supported in the arms of two of his officers, Radcliffe told Cosby:  "I see, Cosby, that I must leave thee to thy baseness, but will tell thee ere I go that it were better to die in the hands of thy countrymen than at my return to perish by my sword".. The half-hearted charge by Cosby turned back and began to retreat. This further demoralised the English forces as they watched their only corps which still showed some rudiments of formation flee the field. At this point, Brian Óg and his 160 heavy Gallowglasses entered the battle, causing panic amongst the English forces:  "Like hounds slipped from the leash, O'Rourke's Brenny men went upon the Queen's vanguard... MacDermott's gunmen and archers gave way to the right hand and to the left, opening out like folding doors as the Brenny men, with a shout at such an instant changed fortitude to alarm, and alarm to panic terror, went upon the foe." The commander of the vanguard, Alexander Radcliffe, could no longer control his troops. They wheeled about in a panic and collided with the main column, which broke and fled. The commander led a charge with his remaining pikemen but was shot dead. With the English ranks in disarray, the main body of Irish infantry, which had concealed itself on the reverse slope of the hill, closed in and fought hand-to-hand. Clifford tried to regain control over his men, but appeared overcome by his circumstances.