Between July 1926 and March 1927, Peng campaigned in Hunan, participating in the capture of Changsha and Wuhan. Under General He Jian, Peng participated in the Battle of Fengtai in which Kuomintang forces decisively defeated the warlord Wu Peifu. In 1927, Wang Jingwei attempted to establish a left-leaning Kuomintang government in Wuhan that threatened Chiang Kai-shek's leadership. Tang Shengzhi, who Peng served under, aligned himself with Wang, and Peng was promoted to lieutenant-colonel and regimental commander. After Tang's forces had bern decisively defeated by Chiang, Peng commanded the rear guard and protected the retreat of Tang's forces into Hunan.