This post was updated for clarity at 5:58 p.m. PT on March 22.

Michael Phelps, 31, the 23-time Olympic gold medalist, paid a surprise visit to USC on Tuesday and was a panelist for an event hosted by USC Annenberg School for Communication and Journalism. The event featured Dick Ebersol, former president of NBC Sports, and included sports journalism professor Alan Abrahamson as a panelist.

"I started with a dream of wanting to change the sport and do something that nobody else has ever done," Phelps said during the event. "Looking back at the 20 plus years I swam, I can say I did it."

When Phelps was 11 he was approached by Coach Bob Bowman, who told him that in four years, Phelps could make the Olympic swimming team. Sure enough, four years later, he appeared in the 2000 Sydney Olympics.

Phelps had a personal relationship with Ebersol, and used to text the Ebersol before his race. "I look at Dick as a father," Phelps said.

Ebersol helped Phelps and his family recover after he was arrested for driving under the influence at 19 and when Ebersol lost his youngest son in a plane crash, Phelps was there to support him.

Phelps said that his fame put his life was under a microscope, which meant that he had to learn hard life lessons early.

"At a young age, I was forced to learn things that a lot of people weren't really forced to learn or really had the chance to go through," Phelps said.

Phelps retired in 2012 after the London Olympics, but came out of retirement for the 2016 Olympics in Rio De Janeiro, where he won five gold medals and one silver medal.

"Being able to come back and finish exactly how you want… I think from a sports perspective, that's the best way to finish a career," Phelps said.

"I will miss not having the chance to listen to the national anthem and see the stars and stripes flying up with a gold medal around my neck," said Phelps. "The coolest thing about being an Olympian is we truly feel the Olympic love, the American love, whenever we are competing in the games."

Reach Staff Reporter Hawken Miller here.