hold/stand your ground
hold (one's) ground
1. To brace oneself and maintain one's position during or in the face of an attack. The other team's offense was incredibly aggressive, but our defense held their ground. Despite the guy's size, I managed to hold my ground during the fight.
2. To refuse to yield, compromise, or be belittled; to stand up against an attack or insult. The boss scoffed at her idea initially, but she held her ground and explained it in greater detail. My wife wanted to take more than half the estate during the divorce, but I stood my ground.