In the winter of that year, the Song people had been preparing for war with all their might. The people raised and strengthened the city walls, hoarded food and grass supplies, made armor and chariots, and built two fortresses outside the city. In short, what a country can do to meet the war, the Song State has done; The people of the Song Kingdom were both scared and excited, and everyone wanted to fight the enemy happily.

In February of the tenth year of the reign of Duke Lu Yin (BC713), Duke Zheng Zhuang, Duke Qi Xu, and Duke Lu Yin met in Zhongqiu, Lu State. Since the current situation has changed a lot compared to last year - the Song State is ready to face the battle, and the plan for the war against the Song must also be adjusted accordingly.

Zheng Zhuang Gong believed that the purpose of the Song Dynasty was to crusade against disrespect, obtain benefits, and weaken the enemy country; Now that Shangqiu is impregnable, the coalition forces can no longer carry out the siege plan formulated last year.

"A fool would attack a well-defended city! The Song State governed several large cities, and there was not only one Shangqiu City. Song and Yi shrank their defensive forces around the national capital, and other cities were bound to be empty. As long as we capture a few big cities and achieve the goal of cutting down the Song Kingdom, the widows can return to the Son of Heaven. If the Song army rushed to the rescue, the enemy was exhausted after a long journey, and our troops were in an advantageous position and could wait for work at leisure, the Song army would definitely be defeated. Zheng Zhuanggong said.

His proposal was adopted. In the summer and May, the Battle of the Song Dynasty officially began. Zheng Jun set out from Xinzheng and traveled all the way north to Jishui, then sailed east along the river, passed through Cao State, and landed at Maodi (north of Shanxian County); Gongzi Hui led the vanguard of the Lu army to the polar region (northwest of Shanxian County); The Qi army was stationed between the Zheng and Lu armies.

The targets of the coalition forces were two large cities of the Song State, one was Gao and the other was Fang. Gao was originally a country, the founding monarch was the son of King Wen of Zhou, and the Gao State was destroyed by the Song State before the Spring and Autumn Period; Fang is also known as "Xiyi" (the land given to Zheng Huan by King Xuan of Zhou is called "Dongyi").

Song Yangong was furious after receiving the information, he first scolded Zheng Zhuanggong's ancestors in turn, and then said hatefully: "Everyone come to see Zheng Ningsheng, this coward!" He didn't dare to start a dignified battle with the Song Kingdom, so he sneaked to the border to do the robbery! The Zheng people dared to be enemies of the Song State with the support of the Qi State and the Lu people, otherwise Zheng Ningsheng would have started a war with the widows last year! Since they bypassed Shangqiu and ran to the east, they don't want to return to China again! The widow is about to exterminate the Zheng people in the thatched land! ”

However, Kong Fujia did not agree with Song Yangong's approach, saying: "The Zheng people did not dare to attack head-on precisely because they were afraid of the strong military power of the Song state; If we disperse our forces to fight with the enemy in the frontiers, we will fall for the enemy's tricks. The minister thought that he could send a small number of troops to strengthen the defense of Gao Hefang. These two towns will definitely be lost, it is only a matter of time before they are lost. But it doesn't matter, because we will surely defeat the enemy in the end, and then the two cities will return on their own.

"Now the main forces of the Zheng army are in the thatched land, and the country is empty; We took this opportunity to raid Xinzheng. When the Zheng people learned that the capital was attacked, they would definitely return to the division in a hurry; Qi and Lu cannot stay alone, and they will also withdraw their troops, and the country's crisis can be solved. If we intercept the retreating Zheng army, we will surely win a great victory. ”

However, Song Yangong had a stubborn temper that would rather rot his entire arm than cut off his fingers, and he stubbornly demanded a decisive battle with the main force of Zheng's army. His plan had nothing to do with courage, he was just more worried about the benefits he was about to lose.

On June 3, Lu Yingong led the main force of the Lu army to the assembly area, and by this time the Song division had already marched towards the Zheng army. The monarchs of Zheng, Qi, and Lu immediately held a meeting, at which the Duke of Qi once again expressed the cautious stance of stopping in moderation and not being too lethal. In view of the attitude of the Duke of Qi, the meeting finally decided that the Zheng army would besiege Gao and Fangliangyi, and the Lu army would intercept the Song reinforcements; The Qi army did not participate in the battle for the time being, but served as a reserve: if an Allied unit encountered an unfavorable situation, the Qi army would quickly support it.

The Song army built a pontoon bridge at the source of Danshui, and after passing through Danshui, the army assembled at Shan Fu (now Shan County), by which time the Zheng army had already surrounded Gaocheng. Gaocheng is about forty miles away from Shan Fu, and the area between the two places is called "Suga"; The Song army was blocked by the Lu army as it passed through Kandi.

As mentioned earlier, Lu Yingong has been looking for an opportunity to take revenge because he has suffered great humiliation from Song Yangong, so this battle is actually a battle for honor.

In fact, the Lu army was at a disadvantage in numbers, and the terrain was not superior, but because the Lu people valued their dignity more than their lives, the offensive was extremely fierce. Their momentum completely suppressed the enemy. As the battle progressed to sunset, the Song army was defeated and forced to retreat to the single father. Early the next morning, a reinforcement army of Qi arrived, and the coalition forces built a solid defensive line in Kanji. The Song army completely lost hope of supporting Gaocheng, but was unwilling to withdraw its troops, so it confronted the coalition army in Shan Father.

The scale of Gaocheng is much larger than that of ordinary cities, and it is located on the border of Song and Shandong. It was the main battlefield of the Song and Lu dynasties during the reign of Lu Huigong, so the defense facilities of Gaocheng were still very complete. However, most of the young and middle-aged people in Gaocheng were requisitioned to Shangqiu, and there were few weapons available in the city, and the defensive strength was seriously insufficient. The defenders then sent an urgent report to the people of Fang, Liangqiu and Chuqiu, but the people in those three places were too busy to take care of themselves, and they were unable to send troops to rescue.

The Zheng Guoren decided to besiege Gaocheng with the method of full flowering, and they made a large number of ladders and siege vehicles. The soldiers waved all their flags, beat all the drums of war, and raised their voices when they attacked.

The soldiers attached themselves to the walls, and the siege vehicles slammed into the gates; The line of defense was full of fires and holes. The Gaocheng people had exhausted all their weapons, and they finally gave up after putting up without losing their dignity.

On 15 June, Zheng's army marched into Gaocheng, and Zheng Zhuanggong allowed the defeated to leave or stay where they were with their possessions, and assured that no one would be hindered or harmed. After that, he handed over Gaocheng to Lu Yingong.

After a short rest, Zheng's army surrounded Fangyi, which was much weaker than Gaocheng's. On June 25, Fangyi fell. Although both cities were captured by the Zheng army, Zheng Zhuanggong only wanted a good reputation for integrity, generosity, and incorruptibility. He gave Fangyi to Duke Qi, but the Marquis of Qi considered that he had no merit, and Fangyi was an enclave, but it was adjacent to the Lu State; Therefore, he did not dare to accept it. In this way, Fangyi was also given to Lu by Zheng Zhuanggong.