Rawdon's advance companies, the light infantry and grenadiers of the Volunteers of Ireland, struck the pickets on Greene's left. The musket fire alerted the Americans, who hurried to get into battle formation.
Meanwhile, Rawdon deployed the first three units in his line of march in attack formation: the British 63rd Regiment on his right, a detachment of the New York Volunteers in the center, and the King's American Regiment on the left.
As the British and Loyalists advanced, they met an unwelcome surprise. Greene's artillery had returned, and the three six-pounders blasted the attackers with grapeshot.
Then the veteran Maryland Continentals joined the combat. Rawdon ordered the Volunteers of Ireland to extend his line on the right, and pressed the attack.