Yang Guozhong
A rivalry soon developed between Yang Guozhong and An Lushan, and Yang Guozhong began to repeatedly warn Emperor Xuanzong that An was plotting rebellion. Emperor Xuanzong ignored the warnings. In 754, Yang Guozhong suggested that if An were summoned to the capital, he would surely refuse, and Emperor Xuanzong decided to try An – and An arrived in Chang'an immediately after being summoned. After this incident, Emperor Xuanzong no longer believed that An was plotting rebellion. Nevertheless, because of Yang Guozhong's opposition, he did not make An chancellor, as he was planning. Also in 754, with Yang Guozhong also trying to squeeze Chen out of the government, Chen resigned and was replaced by Wei Jiansu.