However, breaking the arrangement previously agreed upon proved to be the fateful mistake that Stephen was waiting for all along: on October 26 he ambushed the Poles while they were marching on a narrow road passing through a thickly wooded area known as "The Cosmin Forest". Thus, John I Albert was unable to deploy his forces, rendering the Polish heavy cavalry completely useless. The several phases of battle lasted for three days, with Stephen routing the invading army, which was forced to flee in disarray, harassed all the way by the forces of the prince. At the same time a Moldavian contingent intercepted on October 29 a hastily assembled Polish relief force and completely annihilated it at Lențești.