Zheng Zhu
In 833, Du was sent out of Chang'an to serve as the military governor ("Jiedushi") of Fengxiang Circuit (鳳翔, headquartered in modern Baoji, Shaanxi), as well as the mayor of its capital Fengxiang Municipality. Thereafter, he briefly left government service to observe a mourning period when his mother died. In 834, he was recalled to government service as the military governor of Zhongwu Circuit (忠武, headquartered in Xuchang, Henan). In 835, there was a time when Emperor Wenzong was set to replace him with the general Li Ting (), but Li Ting's commission was cancelled when Emperor Wenzong's close associate Zheng Zhu falsely accused Li Ting of corruption, and Du thus remained at Zhongwu.