Ukraine’s new army chief was key in defending Kyiv against all odds at the start of the Russian invasion. Closing in on the war’s two-year mark, Oleksandr Syrskyi now has the fate of the conflict in his hands.

Syrskyi, 58, was called on by President Volodymyr Zelenskyy to take over as his top general on Thursday in the biggest military shakeup since the start of the war. The commander of Ukraine’s ground forces, he succeeds Valeriy Zaluzhnyi, who was replaced following weeks of speculation about his deepening rift with the president.

Unlike Zaluzhnyi, Syrskyi lacks a broad public profile in Ukraine. Zelenskyy referred to him as Ukraine’s "most experienced” commander, citing his deep involvement in defending the capital during the first phase of the Russian onslaught and the liberation of a swathe of the Kharkiv region later in 2022.