裴度
Later, during the reign of Emperor Dezong's grandson Emperor Xianzong, it was said that because Yang Sifu became well known by the chancellor Wu Yuanheng (along with Pei Du and Liu Gongchuo (), Wu, while later serving as the military governor of Xichuan Circuit (西川, headquartered in modern Chengdu, Sichuan), invited them to serve on his staff. Yang was later recalled to the capital Chang'an to serve as "You Shiyi" (), a low-level advisory official at the legislative bureau of government (中書省, "Zhongshu Sheng"), and also served as an editor of the imperial history. Because Yang was well-learned in the ceremonies, he was later made "Taichang Boshi" (), a scholar at the ministry of ceremonies (太常寺, "Taichang Si").