All through high school, Gonzales saved to pay for a college education. When it became clear that his financial status would not allow him to continue his study of engineering after his first semester at the University of Denver, he went into professional sports. He soon became a featherweight champion, winning a Golden Gloves title, and the National Amateur Athletic Union bantamweight title in 1946.
As a professional boxer, Gonzáles was ranked the number 3 Featherweight boxer by Ring Magazine. He retired from the ring in 1955 after compiling a record of 65 wins, 9 losses, and 1 draw. His success in boxing lent him a prominence that he would later capitalize upon during his political career. Gonzales would be inducted into the Colorado Sports Hall of Fame in 1988.
In his column in the Denver Post of January 6, 1988, Tom Gavin wrote,
"He’s grizzled now, and gray,
but he stands tall, Corky Gonzales does,
and taller still, Rodolfo "I am Joaquin" Gonzales.
The one was a pretty good boxer,
the other is a leader of men."