Zhuge Liang's first Northern Expedition was forced to retreat because Ma Mo lost his guard of the street pavilion. Although the three counties of Nan'an, Tianshui, and Anding surrendered to Zhuge Liang at that time, the situation was very good, but due to the loss of the street pavilion, Zhuge Liang had no basis in front of him, so he had to abandon it.
Later, it was agreed that the appointment of Ma Mo was one of the main reasons for the loss of the street kiosk. If Ma Mo had followed Zhuge Liang's instructions and defended the city, he would certainly not have been defeated. However, Ma Mo gang was self-conscious, and did not listen to Wang Ping's advice, and went up the mountain to defend, and as a result, Zhang Guo cut off the road. The Shu army was chaotic without a fight and was defeated. So, if you don't send a horse, how about replacing someone else? In the "Romance of the Three Kingdoms Chronicles", it is recorded that
In the sixth year of Jianxing, Liang sent an army to Qishan, and sometimes there were generals Wei Yan and Wu Yi, and the commentators all said that it was appropriate to take Order as the vanguard, while Liang violated the crowd and unified the masses, and fought with the Wei general Zhang Gao at the street pavilion, which was broken by Gao and the soldiers were scattered. Liang jin had no basis, and the retreating army returned to Hanzhong.
We can see that at that time, at Zhuge Liang's side, there were such generals as Wei Yan and Wu Yi who could be called at any time, but Zhuge Liang abandoned them and appointed Ma Chen against everyone's opinions. So, Zhuge Liang doesn't need Ma Chen, can he use Jiang Wei and Zhao Yun?
If Zhao Yun is by Zhuge Liang's side, I think he will be more likely to appoint Zhao Yun. Because guarding the street kiosk is not a very difficult thing. Zhuge Liang did not ask Ma Mo to defeat Zhang Guo, he only asked Ma Mo to be able to guard the street pavilion.
After Zhuge Liang left Qishan, because it was the first time he had fought such a big battle, he was very cautious and careful. In addition to sending a part of his small troops to raid various places, the main force was still gathered in his hands. The three counties he received, Nan'an, Tianshui and Anding, were all intimidated into surrendering. Longxi Commandery, on the other hand, hastily mobilized, relying on a group of rabble-rousers, to scare back the Shu army that came to attack. It can be seen that the main force of the Shu army at that time was in the hands of Zhuge Liang.
Zhuge Liang set up his base camp in Xicheng, and the main force was also in this area, and he was ready to fight a decisive battle with the Cao army in this area. He believes that he has the advantage of the home field, Zhang Hao is tired from afar, and there is an opportunity to take advantage of it. Therefore, he sent Ma Mo to the street pavilion to defend, and instructed him to occupy the walled city of the street pavilion, hoping to block Zhang Gao first, and then drag the Cao army into a protracted battle.
Zhang Gao's unit was Cao Wei's Central Mobile Corps, with 50,000 mounted infantry. Zhuge Liang's total strength was only 60,000, and most of them were recruits. Ma Mo led the front soldiers and horses, so that in terms of numbers, he was not Zhang Gao's opponent. Therefore, Ma Mo's ascension to the heights and breaking the enemy is purely an excuse for himself to fear the enemy and avoid war.
If Zhao Yun was here, he would definitely be much stronger than Ma Mo. He experienced the Battle of Hanshui, where he defeated the Cao army. In the face of Zhang Gao's superior troops, he would not be afraid. He was sure to be able to act according to Zhuge Liang's intentions and guard the street kiosk.