2 Samuel 10:9

The front of the battle. As Joab surveyed the situation, he found himself between the Ammonites drawn up in front of their capital, and their allies to the southwest. Whichever force he might choose to attack, he would find the other force at his rear. There were both advantages and dangers in this disposition of the enemy forces, and the keen eye of the experienced Joab took in the whole situation. He began the battle with the forces of the enemy already divided in two. To prevent being attacked in the rear, he divided his own forces into two divisions, one to attack the Ammonites and the other their allies.

All the choice men. The best of the Israelite troops were chosen for the attack on the Syrians, since with their chariots and cavalry they formed the strongest part of the enemy forces. Joab himself took charge of these troops.