Treschov performed his first and only career spacewalk on August 26, 2002.[3] The start of the spacewalk was delayed because of an air leak in the sealed hatches between the Pirs airlock and the Zvezda module. The problem was easily corrected but took Treshchov and fellow cosmonaut Valery Korzun almost a half-hour to step through the procedures and get ready to go outside. Despite the late start at 05:27 UTC, the two spacewalkers finished everything assigned to them on this spacewalk.[4] Wearing Russian Orlan spacesuits Treschov and Korzun installed a frame on the outside of the Zarya module to house components for future spacewalk assembly tasks.