A different account of how Krychevsky joined Khmelnytsky is present in other sources. Taken prisoner by Tatars during the Battle of Zhovti Vody (Yellow Waters) in April/May 1648, where he still fought on the Polish-Lithuanian side against the Cossacks, he was liberated by Khmelnytsky, who convinced him to join his side. Other sources even accuse Krychevsky of joining Khmelnytsky in the midst of the battle, and of meeting (or planning to meet) with him before the battle.