According to a legend, Prince Casimir Jagiellon appeared before the Lithuanian troops and helped them to achieve victory.

[3] According to a legend, recorded by Bernard Wapowski[1] and Marcin Bielski,[2] the Lithuanians could not locate a safe place to cross the river.

However, a young man appeared, dressed in white and riding a fine horse, and rode first into the river leading the Lithuanians safely across only to disappear on the other side.

[1] The soldiers identified the youth as their deceased Prince Casimir, elder brother of Lithuanian Grand Duke Sigismund I the Old.

After crossing, the Lithuanians waited for the night, set hay stacks alight to confuse and disorient the enemy, and swiftly attacked the Russians.