Vytautas, supported by the Polish banners, started an assault on the left flank of the Teutonic forces.[1] After more than an hour of heavy fighting, the Lithuanian light cavalry began a full retreat. Jan Długosz described this development as a complete annihilation of the entire Lithuanian army. According to Długosz, the Knights assumed that victory was theirs, broke their formation for a disorganized pursuit of the retreating Lithuanians, and gathered much loot before returning to the battlefield to face the Polish troops.[59] He made no mention of the Lithuanians, who later returned to the battlefield.