Brooks, a student of Rener Gracie, has been flirting with mixed martial arts since departing the WWE in 2013.
The 6-foot-2 wrestler is currently undecided which weight class he'll aim for, but said on the broadcast that he'll likely target middleweight, although welterweight could be an option as well.
"This is my new career, 100-percent," said Brooks. "I'm going to go full steam ahead, all systems go after today, and it's going to be fun. I have nothing but respect for everybody here at the UFC, everybody who steps in the Octagon to fight. And when it's all said and done, when I'm finished, everybody's going to have to respect me because I have come here to fight."
Brooks, 36, is expected to make his UFC (and mixed martial arts) debut sometime in 2015.
"I felt like it was now or never," Brooks said. "I have a limited window most fighters don't have. I'm either here to win or get my ass kicked."