Final answer:
The phrase refers to an American football strategy where two offensive players block a defender, anticipating a second defender's aggressive play and counteracting it.
Step-by-step explanation:
The phrase 'Double Team One Defensive Player; then Attack Second Blitzing Player' is a strategy used in sports, specifically in American football. This tactic involves two offensive players working together to block a single defensive player, usually to create a hole in the defensive line or to protect the quarterback from being tackled. Then, if a second defensive player attempts to 'blitz' or rush aggressively, the offense would shift their focus to block this new threat. It requires good communication and coordination among teammates to execute effectively.