[take] the flank

to position oneself or others on the side of a group for protection or a strategic advantage, typically in a military context

During the sports game, they took the flank positions to outmaneuver the opposing team.
In the military operation, the soldiers took the flank to provide cover for the main force.
The experienced hikers knew to take the flank while navigating through the challenging terrain.
The security team took the flank positions to secure the perimeter of the event.
In the battle, the skilled archers were instructed to take the flank, ensuring the army's defenses from the side.