A war of nerves
Definition 1 of 1
Pro Tip 1/3Figurative Sense
The phrase is used metaphorically to describe a strategic psychological conflict. 
The two competitors entered a war of nerves, each trying to psych the other out before the race.
Pro Tip 2/3Tension Filled
It refers to a state of ongoing tension without direct confrontation. 
The standoff at the border became a war of nerves, with neither side backing down.
Pro Tip 3/3Anxiety Provoking
It emphasizes wearing down another's emotional stability by creating fear and anxiety. 
In this war of nerves, repeated false alarms were used to disturb the enemy's peace.