In winter 570—as forewarned by the Northern Zhou general Wei Xiaokuan, who advised against the Yiyang campaign—the famed Northern Qi general Hulü Guang left Yiyang and instead advanced onto Northern Zhou territory north of the Fen River (汾水, flowing through modern Linfen), building forts and capturing substantial territory from Northern Zhou. While a counterattack by Yuwen Xian subsequently fought Hulü to a stalemate, damage had been done, and Northern Zhou was further forced to give up on the Yiyang campaign in fall 571 to concentrate against Hulü.