We read all the lead to present a different history.
Throughout history, as military generals, it is often the time to make great achievements in their prime years, after all, they are very energetic on the battlefield, not only to deal with military information and formulate military strategies at any time, but also to travel thousands of miles day and night, as for personally going into battle to kill the enemy, it is even more commonplace. Without a strong physique and strong energy, the military generals would not be able to eat at all on the battlefield. However, there are exceptions, and there are many military generals in Chinese history who have made great achievements in their old age, such as several veteran generals in the Three Kingdoms period- the Shu Han general Huang Zhong and Liao Hua, and the Eastern Wu general Ding Feng. In addition to these three people, there is actually a very powerful veteran, he is the former Liu Zhang's general, BaJun is too strict.

▲Veteran Huang Zhong stills
Regarding Yan Yan's origin and position, the descriptions of the Romance of the Three Kingdoms and the Romance of the Three Kingdoms roughly coincide. The book reads: "BaJun is too strict and strict, is a famous general in Shu, although he is old, his energy has not declined, he is good at opening a hard bow, making a big sword, and has the courage of ten thousand men." At that time, Liu Bei had just sent an army to Yizhou, preparing to seize the land of Bashu as the basis for the king's hegemony, and did not want the important strategist Pang Tong around him to die in Luofengpo, so he sent an order to Jingzhou to support, and Zhuge Liang led Zhang Fei and Zhao Yun to Xichuan in two ways. After entering Sichuan, Zhang Fei led an army to attack the city strategically, and met Yan Yan in Ba County. However, his bravery did not include Zhang Fei, who was captured after more than ten rounds and then surrendered. This is the well-known "righteous interpretation of yan".
▲Zhang Fei and Yan Yan stills
After this, Yan Yan never appeared in the history books again. As for the rendition, Yan Yan's last appearance was during the "Battle of Hanzhong", when he was Huang Zhong's deputy general and recaptured Tiandang Mountain with Huang Zhong, and there has been no description of him since. Speaking of which, Yan Yan was able to fight with Zhang Fei for more than a dozen rounds, proving that his level of strength was not low, and he could also be regarded as a fierce general, after all, he also became famous for this battle. So the question is, since Yan Yan is a fierce general, why didn't he get Liu Bei's reuse? It should be known that Liu Bei did not have many talents under him, and Yizhou lost Jingzhou, so that the Jingzhou clique with high official positions in the Shu Han regime was looked down upon by the Yizhou clique, and the native shi clan in Yizhou was suppressed, which made the successor forces in the Shu Han regime very small.
Speaking of which, the reason is actually very simple. First, too old. Yan Yan is a veteran with the same name as Huang Zhong, and a "old" word is actually enough to indicate that the two are of similar age, so they are compared. In the fourteenth year of Jian'an (209 AD), Huang Zhong and Guan Yu fought in Changsha at the age of 62. In the seventeenth year of Jian'an (212 AD), Zhang Fei attacked Ba County and fought a major battle against Yan Yan. In the twenty-third year of Jian'an (218 AD), Huang Zhong accompanied Liu Bei in his conquest of Hanzhong and captured Tiandang Mountain. According to the time calculation, Huang Zhong was 71 years old at this time, so in comparison, Yan Yan should also be about 70 years old. In his old age, it is really difficult to go to the battlefield again.
▲Painting of tent scenes from the Three Kingdoms period
Second, Yan Yan's mentality is different. As a veteran, Huang Zhong is as fierce as fire, does not accept aging and is eager to make meritorious achievements, which can be seen from his several battles with Wei Yan and Zhao Yun. Yan Yan is different, there is no competitive spirit, and he does not dare to have it. As a general of Yizhou, he did not have Huang Zhong's seniority, and his prestige was not as good as Huang Zhong's, so naturally he did not dare to be as arrogant as Huang Zhong. In the "Battle of Tiandang Mountain", if it were not for Huang Zhong's orders, it is estimated that he would not have gone to the battlefield again. This may also be the sympathy between veteran generals, if Yan Yan is under Zhang Fei and Guan Yu, it is estimated that he will not be allowed to go to the battlefield again, at most he will be responsible for some logistics such as grain and grass escort.
▲ Wei Yan stills
Third, out of the principle of suppressing the Yizhou Group. As we all know, Guan Yu, Zhang Fei, Zhao Yun and other senior former subordinates were Liu Bei's confidants, and Huang Zhong, Wei Yan and other Jingzhou forces were the second supporters, and after the loss of Jingzhou, Wei Yan and others could only be loyal to the Shu Han regime. However, the Yizhou Shi clan was different, they had rejected Liu Bei, and their strength was very strong, but no one integrated, if Liu Zhang had the ability, it was estimated that ten Liu Bei would not be able to defeat him. Therefore, the Shu Han regime had a repressive attitude towards the Yizhou warriors, especially the forces in the military, and there were very few Yizhou generals who could independently control the army. Yan Yan was a representative of the military in Yizhou, and Liu Bei naturally could not reuse him.
▲ Yan Yan was captured stills
In addition, when Zhang Fei captured Yan Yan, Yan Yan once said: "Ru and other unrighteous, invaded our prefecture and county, but there are severed generals, no surrender generals!" In the end, Yan Yan reluctantly surrendered because of Zhang Fei'enyi. It can be said that he was not too willing to surrender to the Liu Bei clique. After Yan Yan surrendered to Zhang Fei, he easily recruited various city guards along the way, which also showed that Yan Yan had deep roots in the Yizhou Army. Liu Bei would naturally be wary of threatening the Shu Han Dynasty with the whole army after he took charge of the army. Therefore, the three reasons of old age, his own indisputability, and Liu Bei's suppression gradually disappeared after Yan Yan's surrender.
Resources:
Romance of the Three Kingdoms, Huayang Chronicle