Describe symbolism in The Brave by Robert Lipsyte

In Chapter Eighteen, Brooks supported Sonny during the fight, and Sonny's perspective on the monster began to change. He started to feel as if they were wings were rustling inside him. This is symbolic of the hawk that Jake always said resided within him. He was gaining strength as a controlled fighter, but had a long way to work before he got to the top. He had to learn to take control of the monster and use it as a positive energy in his own fighting.