Turenne began the battle with four or five artillery salvoes from his two unopposed batteries, and the Spanish right flank was bombarded with some harassing fire from several frigates and sloops of the English fleet. The Anglo-French army began to advance, and the Cromwellian English pressed quickly ahead against the Spanish tercio of Don Caspar Boniface deployed on a sand dune that was somewhat in advance of the rest of their army. The English charged and crossed pikes with the Spanish tercio, driving it down the hill, and, by following up, the English formation became exposed. James, Duke of York, led two cavalry charges against the Cromwellian troops' flank, driving into the musketeers. Some Spanish cavalry from their reserve was sent forward and threatened the English but were defeated in turn by the French cavalry under Marquis de Castelneau. The French infantry consisting of the Guards, the Swiss and the regiments of Picardy and Turenne advanced on the Spanish centre, meeting little resistance. Marshal Turenne took advantage of the receding tide to concentrate most of his cavalry on his left, and its advance enveloped the Spanish right wing.