Battle of Duangu 段谷之戰

After the siege of Didao was lifted in the 2nd year of Zhengyuan (255), Deng Ai became General Who Pacifies the West and Colonel Protector of the Eastern Qiang. Most of those in the debate said that Jiang Wei's strength was already exhausted and he could not come out again, but Deng Ai, saying that the defeat at Taoxi was no small setback, cited five points: the enemy rode the momentum of victory while their own side was weak; the enemy's ranks were well drilled together and its weapons sharp, while their own commanders and troops were new; the enemy traveled by boat while they went by land; they had to divide their forces to guard Didao, Longxi, Nan'an and Mount Qi; and the enemy could eat the Qiang grain in Nan'an and Longxi and the ripe wheat at Mount Qi, so it would surely come. Records, Wei 28 §63–64

In Shu, Jiang Wei was promoted to General-in-Chief in the spring of the 19th year of Yanxi (256). Jiang Wei put his troops and horses in order again and arranged to meet the Senior General Who Guards the West Hu Ji at Shanggui. Records, Shu 14 §38Records, Shu 3 §36

Before long Jiang Wei did indeed head for Mount Qi, but hearing that Deng Ai was already prepared, he changed direction and headed from Dongting toward Nan'an. Deng Ai occupied Mount Wucheng to oppose him. When Jiang Wei contended with Deng Ai for the rugged ground and could not win, that night he crossed the Wei River, went east and headed along the mountains for Shanggui, and Deng Ai fought him in the Duan Valley and heavily defeated him. Records, Wei 28 §65

The Biography of Jiang Wei records that because Hu Ji broke his promise and did not come, Jiang Wei was defeated by Deng Ai in the Duan Valley, his men scattering like stars and wandering, with very many dead. The dates differ from volume to volume. The Annals of the Three Young Emperors say that on the guiwei day of the 7th month of the 1st year of Ganlu the General Who Pacifies the West Deng Ai heavily defeated Jiang Wei at Shanggui, while the Biography of the Later Ruler records that in the autumn, in the 8th month, Jiang Wei was defeated by Deng Ai at Shanggui. Records, Shu 14 §38Records, Wei 4 §76Records, Shu 3 §36

The Wei court issued an edict saying that the heads taken and prisoners captured often ran into the tens of thousands and that no recent victory had matched it, and had the officers and men rewarded and feasted. For Deng Ai, saying that he had beheaded more than ten commanders and taken heads by the thousand, it made him General Who Guards the West and Commander of All Military Affairs in Longyou, promoted him in enfeoffment to Marquis of Deng, and divided off 500 households to enfeoff his son Deng Zhong as a village marquis. In Shu the common people grumbled and the region west of Long was in turmoil, and Jiang Wei, returning to Chengdu, apologized for his fault and asked to be demoted, acting as General-in-Chief while holding the rank of General of the Rear. Records, Wei 4 §76Records, Wei 28 §65–66Records, Shu 14 §38Records, Shu 3 §36