Li Jing was ordered to lead Zuo Jingwei to test the situation of the Tang army's camp. However, he did not launch a direct attack. Instead, he ordered Huang Mingxu to lead his cavalry to outflank the Tang army and detour to the south to prevent the Tang army from escaping.
The Tang army seemed to have given up on defense in front of the formation and retreated to the south bank of the Zhupi River to set up formation.